: 

t 


Smiting  aub  ITabor, 

LIBRARY 


| University  of  Illinois.  | 

| 5S'aiLu®TfficMS'  I 


CENTRAL  CIRCULATION  BOOKSTACKS 


The  person  charging  this  material  is  re- 
sponsible for  its  return  to  the  library  from 
which  it  was  borrowed  on  or  before  the 
Latest  Date  stamped  below. 

Theft,  mutilation,  and  underlining  of  books  are  reasons 
for  disciplinary  action  and  may  result  in  dismissal  from 
the  University. 

TO  RENEW  CALL  TELEPHONE  CENTER,  333-8400 
UNIVERSITY  OF  ILLINOIS  LIBRARY  AT  URBAN A-CHAMPAIGN 


When  renewing  by  phone,  write  new  due  date  below 


A MANUAL 


OF  THE  PRINCIPAL 

REMOTE  STORAGE  . , 

INSTRUMENTS 

i 

USED  IN 

American  Engineering  and  Surveying, 

MANUFACTURED  BY 


W.  & L.  E.  GURLEY, 

TROY,  N.  Y.,  U.  S.  A. 


THIRTY-SIXTH  EDITION . 


TROY,  N.  Y. 

PUBLISHED  BY  W.  & L.  E.  GURLEY, 
APRIL,  1902. 


PRICE , 50  CENTS. 


(y7°\  k 5-yv \.3£ 


\ 


Entered,  according  to  Act  of  Congress,  in  the  Year  1902, 
By  W.  & L.  E.  GURLEY, 

In  the  Office  of  the  Librarian  of  Congress,  at  Washington. 


THE 

MATTHEWS  -NORTHRUP 
• WORKS • 
BUFFALO 





GURLEY’S  INSTRUMENT ‘MANUFACTORY.— Established  1845. 


o3o  4 o 


1845-1902. 


» 


Preface  to  the  Thirty-Sixth  Edition. 


APRIL,  1902. 


EARLY  SIXTY  YEARS  AGO  the  manufacture  of 
**  ^ Civil  Engineers’  and  Surveyors’  instruments  was 
begun  in  this  city  by  Jonas  H.  Phelps  and  William  Gurley 
Mr.  Phelps  retiring  some  years  later,  Lewis  E.  Gurley 
formed  with  William  Gurley  the  firm  of  W.  & L.  E.  Gurley: 
and  under  this  name  the  business  has  since  been  conducted. 

The  first  edition  of  Gurley’s  Manual  was  published  in 
1855,  a book  of  seventy  pages.  It  was  well  received,  and 
was  the  first  really  practical  treatise  on  the  use  and  adjust- 
ment of  Civil  Engineers’  and  Surveyors’  instruments. 

The  revised  and  enlarged  Manual  is  used  as  a text- 
book in  many  schools  and  colleges,  and  is  freely  quoted  in 
technical  publications. 

The  capacity  of  the  factory  has  been  increased  as  the 
demands  of  the  profession  have  grown  during  the  half  cen- 
tury, until  we  are  now  the  most  extensive  manufacturers  of 
Civil  Engineers’  and  Surveyors’  instruments  in  the  world. 

We  expect  to  have  our  instruments  judged  upon  their 
merits,  and  any  Surveyor  or  Civil  Engineer  who  will  care- 
fully examine  our  work  will  be  pleased  with  it. 

W.  & L.  E.  GURLEY, 

Troy,  N.  Y.,  U.  S.  A. 


4 


TRANSIT-INSTRUMENTS. 


' I "HE  AMERICAN  TRANSIT,  in  its  various  modifica- 
A ti9ns,  is  by  far  the  most  important  of  all  the  instru- 
ments used  in  engineering.  The  essential  parts,  as  shown 
in  the  cuts,  are  the  Telescope  with  its  axis  and  two  stand- 
ards, the  Circular  Plates  with  their  attachments,  the 
Sockets  upon  which  the  plates  revolve,  the  Leveling-Head, 
and  the  Tripod  upon  which  the  whole  instrument  stands. 

The  Telescope  is  from  ten  to  eleven  inches  long,  firmly 
secured  to  an  axis  having  its  bearings  nicely  fitted  in  the 
standards,  enabling  the  telescope  to  tran- 
telescope.  g*t  rphe  different  parts  of  the  telescope 

are  shown  on  page  7. 

The  object-glass  is  a compound  lens,  achromatic,  and 
showing  objects  without  distortion,  and  is  placed  at  the 
end  of  a slide  having  two  bearings,  one 
object-glass.  end  of  the  outer  tube,  the  other 

in  the  ring,  C C,  suspended  within  the  tube  by  four  screws, 
only  two  of  which  are  shown  in  the  cut. 

In  Transits  Nos.  1 to  90  both  object-glass  and  eyepiece 
are  moved  out  or  in  by  pinions  working  in  racks  attached 
to  their  slides,  and  are  thus  adjusted  to  proper  focus. 

The  eyepiece  is  made  up  of  four  lenses,  which,  begin- 
ning at  the  eye  end,  are  called  respectively  the  eye,  the 
field,  the  amplifying,  and  the  object  Jens, 
the  whole  forming  a compound  microscope 
having  its  focus  in  the  plane  of  the  cross-wire  ring,  B B. 

In  Transits  Nos.  100  to  105  the  eyepiece  is  focused  by  a 
spiral  movement. 


EYEPIECE. 


5 


6 


TRANSIT-INSTRUMENTS. 


NO  12.  J . , 

Engineers’  Transit,  two  verniers  to  limb,  with  5-inch  needle,  plain  telescope  and  tnpo  . 

Price  as  shown,  $150.00. 


TRA  NS  I T -INS  TR  UMENTS. 


7 


Sometimes  an  eyepiece  with  two 
lenses  is  employed  ; but  this,  while  it 

inverting  gives  more  light,  in- 
eyepiece.  verts  the  image  of  the 
object  seen,  and  is  rarely  used  by 
American  engineers. 

The  object-glass,  receiving  the  rays 
of  light  which  proceed  from  all  the  points 

of  a visible  object,  con- 

VISION  AIDED  J 7 

by  verges  them  to  a focus 

telescope.  at  the  cross-wires,  and 
there  forms  a minute,  inverted  image, 
which  may  be  seen  by  placing  a piece  of 
ground  glass  to  receive  it  at  that  point. 

The  eyepiece,  acting  as  a compound 
microscope,  magnifies  this  image,  re- 
stores it  to  its  natural  position,  &nd  con- 
veys it  to  the  eye. 

The  visual  angle  which  the  image 
there  subtends  is  as  many  times  greater 

MAGNIFYING  ^an  w^ich  would 

power.  be  formed  without  the 

use  of  the  telescope,  as  the  number 
which  expresses  its  magnifying  power2 
is  greater  than  unity.  Thus,  a tele- 
scope which  magnifies  twenty  times  in- 
creases the  visual  angle  just  as  much, 
and  therefore  diminishes  the  apparent 
distance  of  the  object  twenty  times  ; 
or,  in  other  words,  it  will  show  an  object 
two  hundred  feet  distant  with  the  same 
distinctness  as  if  it  were  only  ten  feet 
distant  from  the  naked  eye. 


8 


TRANSIT-INSTRUMENTS. 


HIGH  POWERS. 


It  might  be  supposed  that  the  greater  the  power  of  a 
telescope  the  better  ; but,  beyond  a certain  limit,  this  is 
found  to  be  incorrect.  As  only  a given 
amount  of  light  can  enter  the  object-glass, 
the  more  the  object  is  magnified  the  less  clear  and  bright 
will  it  appear.  We  have  found  that  a power  of  from 
twenty  to  twenty-four  diameters  in  the  telescopes  of 
Transits  gives  the  best  results,  and  is  sufficient  for  all 
ordinary  practice. 

The  cross  wires  are  two  wires  of 
very  fine  platinum,  cemented  into 

the  cuts  on  the  sur- 

CROSS-WIRES.  r r . . 

face  of  a metal  ring. 

They  are  placed  at  right  angles  with 
each  other,  so  as  to  divide  the  open 
space  in  the  center  into  quadrants. 

To  remove  the  cross-wire  ring, 
take  out  the  eyepiece  together  with 
the  little  ring  by  which  it  is  centered,  and  having  removed 
two  opposite  cross-wire  screws,  with  the  others  turn  the  ring 
until  one  of  the  screw  holes  is  brought  into  view  from  the 
open  end  of  the  telescope  tube  ; in  this  screw  hole  thrust#a 
pointed  splinter  of  wood  or  a small  wire,  to  hold  the  ring 
when  the  remaining  screws  are  withdrawn  ; the  ring  can 
then  be  taken  out.  It  may  be  replaced  by  returning  it  to 
its  position  in  the  tube,  and  when  either  pair  of  screws  is 
inserted,  the  splinter  or  wire  is  removed,  and  the  ring  is 
turned  until  the  other  screws  can  be  replaced. 

Care  must  be  taken  that  the  face  of  the  diaphragm  is 
turned  toward  the  eyepiece.  When  this  has  been  done, 
the  eyepiece  is  inserted,  and  its  centering-ring  brought 
into  such  a position  that  the  screws  in  it  can  be  replaced, 
and,  then,  after  screwing  to  the  end  of  the  telescope  the 


TRA  NS IT- INS  TR  UMENTS. 


9 


ring  into  which  the  eyepiece  is  fixed,  the  operation  will  be 
complete. 

The  advantage  of  platinum  over  spider-web  for  the 
cross  wires  of  telescopes  has  long  been  conceded,  but  the 

platinum  difficulty  of  procuring  it  of  sufficient  fine- 
cross-wi res.  ness  has  prevented  its  general  use.  We 
are  successfully  drawing  platinum  wires  of  from  one  eight- 
thousandth  to  one  twelve-thousandth  of  an  inch  in  diam- 
eter, and  are  using  them  in  the  telescopes  of  all  our  instru- 
ments. These  wires  are  perfectly  opaque,  and,  of  course, 
entirely  unaffected  by  moisture  ; and  are  universally  pre- 
ferred to  the  spider-web  heretofore  used. 

The  intersection  of  the  wires  forms  a minute  point 
which,  when  adjusted,  determines  the  optical  axis  of  the 

telescope  and  enables  the  surveyor  to  fix  it 

OPTICAL  AXIS.  . 

upon  an  object  with  the  greatest  precision. 

The  imaginary  line  passing  through  the  optical  axis  of  the 
telescope  is  called  the  “line  of  collimation,”  and  the  opera- 
tion of  bringing  the  intersection  of  the  wires  into  the  optical 
axis  is  called  the  “ adjustment  of  the  line  of  collimation. ” 
This  is  described  on  pages  20-22. 

The  openings  in  the  telescope  tube  are  made  larger 
than  the  screws  used  in  adjusting  the  cross- wires,  so  that, 
when  the  screws  are  loosened,  the  ring  can  be  rotated  for  a 
short  distance  in  either  direction.  The  object  of  this  will 
be  seen  more  plainly  when  we  describe  the  means  by  which 
the  wire  is  made  truly  vertical. 

The  sectional  view  of  the  telescope  also  shows  two 
movable  rings,  one  placed  at  A A,  the  other  at  C C,  which 
are  used  respectively  in  centering  the  eyepiece  and  in  the 
adjustment  of  the  object-glass  slide. 

The  centering  of  the  eyepiece  is  performed  after  the 
wires  have  been  adjusted,  and  is  effected  by  moving  the 


10 


TRA  NS  IT-  INS  TR  UMENTS. 


ring,  by  means  of  the.  screws  shown  on  the  outside  of  the 
tube,  until  the  intersection  of  the  wires  is  brought  into  the 
center  of  the  field  of  view. 

The  adjustment  of  the  object-glass  slide,  which  is 
described  on  page  23,  keeps  the  line  of  collimation  in 
adjustment  through  the  whole  range  of  the  slide,  prevent- 
ing, at  the  same  time,  what  is  called  the  “ traveling  ” 
of  the  wires.  This  adjustment,  which  is  peculiar  to  our 
telescopes,  is  always  made  in  the  process  of  construction, 
and  needs  no  further  attention  from  the  engineer. 

The  Stadia  is  a compound 
cross-wire  ring  or  diaphragm, 

as  shown,  having 
stadia.  tjiree  horizontal 

wires,  of  which  the  middle 
one  is  cemented  to  the  ring 
as  usual,  while  the  others 
are  fastened  to  slides,  held 
apart  by  springs  and  actuated  by  independent  screws,  by 
which  the  distance  between  the  two  movable  wires  can 
be  adjusted  to  include  a given  space,  as  one  foot  on  a 
rod  one  hundred  feet  distant. 

These  wires  will  in  the  same  manner  include  two  feet  on 
a rod  two  hundred  feet  distant,  or  half  a foot  at  a distance 
of  fifty  feet,  and  so  on  in  the  same  proportion,  thus  furnish- 
ing a means  of  measuring  distances,  especially  over  broken 
ground,  more  easily  and  even  more  accurately  than  with 
a tape  or  chain.  We  put  stadia  wires  in  all  Transit  tele- 
scopes without  extra  cost,  if  requested  when  the  instrument 
is  ordered. 

While  more  convenient  to  make  stadia  measurements 
from  the  center  of  the  instrument,  the  increasing  use  of  the 
stadia  demanding  measurements  made  with  the  utmost  ac- 


TRANSIT-INSTR  UMENTS. 


11 


curacy  and  for  shorter  distances  compels  the  use  of  the  “ con- 
stant”; that  is,  the  wires  are  adjusted  to  read  one  foot  on  the 
rod  at  a distance  from  the  center  of  the  instrument  of  100 
feet  plus  c plus  f;  c being  the  distance  of  the  object-glass 
from  the  center  of  the  instrument,  found  by  measuring 
from  the  center  of  the  axis  to  the  shoulder  of  the  setting  of 
the  object-glass  when  it  is  focused  on  a distant  object; 
and  f being  the  focal  length  of  the  object-glass,  found  by 
measuring  from  the  cross-wires  to  the  object-glass. 

The  reason  of  this  is  because  the  rays  cross  each  other 
so  that  the  vertex  of  the  visual  angle  is  not  at  the  center 
of  the  instrument  but  at  a distance  in  front  of  the  object- 
ive equal  to  its  focal  length. 

The  “ constant  ” for  each  instrument,  or  distance  of  the 
zero  of  the  indicated  distance  in  front  of  the  center  of 
the  instrument,  is  noted  on  a card  placed  on  the  inside  of 
the  instrument  box. 

For  example,  in  our  eleven-inch  telescopes,  such  as  are 
used  with  our  larger  transits,  <:  = 5.6  inches  and  /=8.2 
inches  ; c + /.=  1.15  feet.  In  our  Mountain  Transit  tele- 
scopes, c=  4 inches  and /=  5.4  inches  ; c + f = 0.783 
feet.  In  our  Reconnoissance  Transit  telescopes,  c = 4.25 
inches  and  f — 5.75  inches  ; c + /=  0.833  feet. 

The  stadia  wires  are  ordinarily  arranged  so  that  they 
are  seen  at  the  same  time  as  the  cross-wires.  We  arrange 
disappearing  ^em,  when  desired,  so  that  they  are  out 
stadia.  of  focus  when  the  main  wires  are  visible, 
or  vice  versa.  Many  engineers  prefer  this  method,  as 
being  less  confusing  to  the  observer  and  lessening  the  lia- 
bility for  errors  in  observation. 

fixed  The  stadia  wires  are  fixed, \ when  desired,  on 
stadia,  the  same  ring  with  the  cross-wires.  In  such  case 
the  customer  should  clearly  specify  whether  he  wishes  to 


12 


TRANSIT-INSTR  UMENTS. 


measure  distances  from  the  center  of  the  instrument,  or  to 
use  a “ constant.” 

The  Dust-Guard  to  the  object-glass  slide,  as  seen  in  the 
cut,  is  placed  on  the  telescopes  of  Transits  Nos.  1,  to  90, 
dust-  and  Nos.  110  to  117.  This  guard  effectively 
guard,  shields  the  object-glass  slide,  and  prevents  any 
dust  or  foreign  sub- 
stance from  interfering 
with  the  perfect  action 
of  the  slide.  The  cost 
of  placing  the  guard 
on  an  old  Transit  of 
our  manufacture  is 
$4.00. 

With  the  telescope  of  the  ordinary  Transit  it  is  impos- 
sible to  focus  on  objects  at  a distance  of  less  than  ten  feet. 
SHORT  In  order  to  overcome  this  difficulty  and  to  enable 
focus,  the  observer  to  see  objects  near  the  instrument,  we 
have  recently  introduced  an  important  modification  of  the 
telescopes  used  on  Transits  Nos.  1-90,  so  that  they  can  be 
focused  on  an  object  at  a distance  of  four  feet  from  the 
instrument. 

To  enable  the  Transit,  when  desired,  to  be  set  under  a 
center  given  point,  we  now  place  in  the  top  of  the  ball 
point,  of  the  telescope  axis  and  directly  over  the  center 
of  the  instrument  a small  conical  hole  or  “ center  point.” 

The  Standards  of  the  Transit  are  firmly  attached  by 
their  expanded  bases  to  the  upper  plate,  one  of  them  having 
near  the  top,  as  shown  on  page  38,  a little 
standards.  actuatec|  ky  a screw  underneath,  by 

which  the  telescope  axis  is  made  truly  horizontal,  as  de- 
scribed on  page  22. 

The  Magnetic  Needle  is  from  three  and  one-half  to  six 


NO.  154. 


TRANSIT-INSTR  UMENTS. 


13 


inches  long  in  the  different  sizes  of  Transits,  its  brass  cap 
magnetic  having  inserted  in  it  a jeweled-center  of  special 
needle,  shape  and  perfectly  polished,  and  this,  resting 
upon  the  hardened  and  polished  point  of  the  center-pin, 
allows  the  needle  to  play  freely  and  settle  in  the  magnetic 
meridian. 

The  needle  has  its  north  end  designated  by  a scollop  or 
other  mark,  and  on  its  south  end  is  a small  coil  of  fine  brass 
wire,  easily  moved  so  as  to  bring  both  ends  of  the  needle 
to  the  same  level.  The  needle  is  lifted  from  the  pin  by  a 
lever  concealed  underneath  the  upper  plate,  actuated  by  a 
screw  shown  above,  thus  raising  the  button  so  as  to  check 
the  vibration  of  the  needle,  or  bring  it  up  against  the  glass 
when  not  in  use,  and  avdid  the  unnecessary  wear  of  the  pivot. 

The  form  of  the  needle  is  varied  according  to  the  taste 
or  fancy  of  the  maker  or  surveyor,  but  may  be  resolved 
into  two  general  classes,  one  having  the  greatest  breadth 
in  a horizontal,  the  other  in  a vertical,  direction. 

We  usually  make  our  needles  about  eight  one-hundredths 
of  an  inch  broad,  and  about  three  one-hundredths  of  an 
inch  thick,  with  the  ends  brought  to  a sharp  vertical  edge  ; 
but  whenever  desired  we  supply  other  forms. 

The  test  of  the  delicacy  of  a magnetic  needle  is  the 
number  of  horizontal  vibrations  which  it  will  make  in  a 
certain  arc  before  coming  to  rest ; besides  this,  most  sur- 
veyors prefer  to  see  also  a quivering  motion. 

This  quality,  which  is  manifested  more  in  a horizontal 
than  in  a vertical  needle,  depends  upon  the  near  coinci- 
dence of  the  point  of  suspension  with  the  center  of  gravity 
of  the  needle,  and  merely  serves  to  show  that  the  cap  is 
unobstructed. 

The  compass-box  containing  the  needle  is  covered  by  a 
glass  to  exclude  the  moisture  and  air ; the  circle  is  silvered 


14 


TR  A N SI  T-  IN’S  TR  UMENTS. 


and  divided  on  its  upper  surface  into  degrees  and  half 
degrees,  and  figured  from  0 to  90  on  each  side  of  the  line 
of  zeros  ; the  degree  marks  are  also  cut  down  on  the  inner 
edge. 

A variation  arc,  for  setting  off  the  variation  of  the 
variation  needle,  is  furnished  with  any  new  Engineers’ 

ARC.  Transit,  Nos.  1 to  16,  if  ordered  with  the 
instrument,  at  an  extra  cost  of  $4.00. 

The  Clamp  and  Tangent  movement  has  its  tangent 
CLAMP  and  screw  with  opposing  spring  attached  to  the 
TANGENT,  upper  plate,  as  shown  on  page  6;  the  clamp  is 
shown  in  the  sectional  cut  on  page  15,  being  a strong  metal 
ring,  D F,  moving  easily  around  the  solid  outer  socket,  to 
which  it  is  securely  fixed  at  will  a clamp-screw,  E,  im- 
pinging upon  a segment,  F.  By  this  means  the  plates  are 
clamped,  and  moved  slowly  around  each  other  in  either 
direction  by  the  tangent  screw,  or  loosened  at  will  and 
moved  by  the  hand,  the  telescope  being  thus  easily  and 
accurately  directed  to  the  point  of  sight. 

The  two  levels  are  placed  at  right  angles  with  each  other 
so  as  to  level  the  plate  in  all  directions,  and  are  adjusted 
by  turning  the  capstan-head  nuts  at  their 
PLATE- levels.  encjs  a small  steel  adjusting-pin.  The 

glass  vials  used  in  the  levels  of  all  our  Transits  are  ground 
on  their  interior  surface,  so  as  to  give  the  bubble  an  even 
motion  and  great  sensitiveness. 

The  Lower  Plate,  or  Limb  (at  B in  the  cut  on  page  15) 
horizontal  *s  divided  on  its  upper  surface,  usually  into 
limb.  degrees  and  half  degrees,  and  figured  in 

two  rows,  from  0 to  360  and  from  0 to  90  each  way  ; some- 
times but  a single  series  is  used,  and  then  the  figures  run 
from  0 to  360  or  from  0 each  way  to  180.  The  figuring 
may  be  varied  according  to  the  wish  of  the  person  ordering 


TRANSIT-INS  TR  UMENTS . 


15 


the  instrument,  the  double  series  being  always  used  unless 
otherwise  specified. 

The  Verniers,  V V,  are  attached  to  the  upper  plate 
diametrically  opposite  to  each  other,  and  are 

VERNIERS 

used  in  reading  the  limb  within  which 

they  revolve. 

The  verniers  are  double,  having  on  each  side  of  the 
zero  mark  thirty  equal  spaces  corresponding  precisely 
with  twenty-nine  half  degrees  of  the  limb  ; they  thus 
read  to  single  minutes,  and  the  number  passed  over 
is  counted  in  the  same  direction  in  which  the  vernier  is 
moved. 

The  verniers  are  placed  in  front  of  the  observer  and  at 
an  angle  of  thirty  degrees  with  the  telescope,  so  that  they 
are  easily  read  without  a change  of  position. 


THE  SOCKETS  AND  CIRCULAR  PLATES. 


16 


TRANSIT-INS  TR  UMENTS. 


The  use  of  two  opposite  verniers  gives  the  means  of 
cross-questioning  the  graduations,  the  perfection  with 
which  they  are  centered  and  the  dependence  which  can  be 
placed  upon  the  accuracy  of  the  angles  indicated. 

Sometimes  a smaller  reading  than  minutes  is  desired, 
and  then  the  spaces  of  the  limb  and  vernier  are  both 
made  proportionately  less,  so  as  to  give  readings  to  thirty, 
twenty,  or  even  ten  seconds  of  arc,  if  required.  The  ver- 
nier openings  are  covered  with  glass,  carefully  cemented 
to  exclude  moisture  and  dust. 

Reflectors  of  celluloid,  as  in  the  Mountain  Transit, 
are  often  used  to  throw  white  light  upon 

R E FLECTO  RS 

the  divisions,  and  shades  of  ground  glass 
are  sometimes  used  to  give  a more  subdued  light. 

The  Graduations  were  formerly  made  on  the  brass 
surface  of  the  limb,  afterward  filled  with  black  wax,  and 
then  finished  and  silvered.  The  limbs  of 
graduations.  ajj  our  Transits  are  now  COyered  with 

sterling  silver ; the  graduations  are  much  finer  and 
more  distinct,  and  the  surfaces  less  liable  to  become  tar- 
nished. 

This  improvement,  which  costs  quite  a large  sum,  we 
make  without  additional  charge. 

To  make  possible'the  utmost  accuracy  of  graduation,  the 
limbs  of  our  Transits  are  polished  and  the  figures  engraved 
before  cutting  the  divisions,  thus  avoiding  any  possible 
chance  for  molecular  change  after  the  graduation  is  made. 

The  Sockets  of  the  Transit  are  compound  ; the  interior 
spindle  attached  to  the  vernier  plate  turning  in  the  exterior 
socket,  C,  when  an  angle  is  taken  on  the  limb; 

SOCKETS 

but  when  the  plates  are  clamped  together  the 
exterior  socket  itself,  and  with  it  the  whole  instrument, 
revolves  in  the  socket  of  the  leveling-head. 


TRA  N SIT- INS  TR  UMENTS. 


17 


The  sockets  are  made  with  the  greatest  care,  the  sur- 
faces being  truly  concentric  with  each  other,  and  the  com- 
position of  which  they  are  made  being  of  different  degrees 
of  hardness,  so  as  to  cause  them  to  move  upon  each  other 
easily  and  with  the  least  possible  wear. 

The  Leveling-head  consists  of  two  plates  connected  by 
a socket,  having  at  its  end  a hemispherical  nut  fitting  into 


made  parallel  at  will  by  four  leveling-screws. 

The  screws  are  of  bronze,  and  are  fitted  to  long  nuts  in 
the  upper  leveling  plate.  They  are  protected  from  dust  by 
brass  covers  screwed  on  the  upper  ends  of  the  nuts. 

The  screws  rest  in  cups  or  sockets,  in  which  they 
turn  without  marring  the  surface  of  the  lower  plate, 
the  cups  also  permitting  the  screws  to  be  shifted  from 
side  to  side,  or  turned  in  either  direction  on  the  lower 
plate. 

The  clamp  and  tangent  movement  of  the  leveling-head, 
partially  shown  on  page  6,  serves  to  turn  the  whole  instru- 
ment upon  its  sockets,  so  as  to  fix  the  telescope  with  preci- 
sion upon  any  given  point,  and  when  unclamped  allows  it  to 
be  directed  approximately  by  hand.  The  tangent  screw  is 
single,  as  shown,  and  has  an  opposing  spring  by  which  ^ost 
motion  is  avoided  and  a very  fine  and  prompt  movement 
secured. 

The  lower  leveling-plate  is  made  in  two  pieces,  the 
upper  one,  which  is  screwed  fast  to  the  top  of  the  tripod, 


center.  the  smaller  lower  plate  is  shifted  from  side  to 
side.  By  this  simple  arrangement,  called  a “ shifting 
center/’  the  instrument  is  easily  moved  over  the  upper 
plate,  and  the  plummet  which  hangs  from  the  center,  P, 


a corresponding  cavity  in  the  lower  plate. 
The  plates  are  inclined  to  each  other  or 


SHIFTING 


having  a large  opening  in  the  center,  in  which 


18 


TRANSIT-INS  TR  UMENTS. 


(see  page  15,)  may  be  set  precisely  over  a point  without 
moving  the  tripod. 

The  Tripod  has  a head  of  bronze  with  three  strong 
tenons  to  receive  the  legs,  the  upper  ends  of  which  are 
pressed  firmly  on  each  side  of  the  tenon  by  a 
bolt  and  nut  on  opposite  sides  of  the  leg  ; the 
nut  can  be  screwed  up  at  will,  and  thus  kept  firm. 

The  lower  end  of  the  leg  has  a brass  shoe  with  steel 
point,  securely  fastened  and  riveted  to  the  wood. 

For  various  patterns  of  tripods  see  pages  176-179. 

. TO  USE  THE  TRANSIT. 

The  instrument  should  be  set  up  firmly,  the  tripod  legs 
being  pressed  into  the  ground,  so  as  to  bring  the  plates  as 
nearly  level  as  convenient ; the  plates  should  then  be  care- 
fully leveled  and  properly  clamped. 

For  precise  work,  in  addition  to  leveling  by  the  plate 
levels,  it  is  always  advisable,  if  the  Transit  has  such  attach- 
ment, to  level  the  plates  by  the  telescope  level,  as  this  is 
much  more  sensitive  than  the  levels  on  the  plate. 

It  must  be  carefully  noted  that  in  this  operation  the 
position  of  the  level  on  telescope  must  be  observed  over 
both  sets  of  leveling-screws,  and  one-half  the  correction 
made  by  the  axis  tangent,  the  other  half  by  the  leveling- 
screws. 

The  zeros  of  the  verniers  and  limb  should  be  brought 
into  line  by  the  tangent  screw  of  the  plates  and  the  tele- 
scope directed  to  the  object  by  the  tangent  screw  of  the 
leveling-head. 

The  angles  taken  are  then  read  off  upon  the  limb,  with- 
out subtracting  from  those  given  by  the  verniers  in  any 
other  position. 


TRA  N SIT- INS  TR  UMENTS. 


19 


Before  an  observation  is  made  with  the  telescope,  the 
eyepiece  should  be  focused  by  its  pinion  until  the  cross- 
wires appear  distinct  to  the  eye  of  the  observer  ; the  object- 
glass  is  then  focused  by  its  pinion  until  the  object  is  seen 
clear  and  well-defined,  and  the  wires  appear  as  if  fastened 
to  its  surface. 

The  intersection  of  the  wires  (the  means  by  which  the 
optical  axis  of  the  telescope  is  defined)  should  be  brought 
precisely  upon  the  middle  of  the  object  to  which  the 
instrument  is  directed. 

TO  ADJUST  THE  TRANSIT \ 

Every  instrument  should  leave  the  hands  of  the  maker 
in  complete  adjustment,  but  all  are  so  liable  to  derange- 
ment by  accident  or  careless  use  that  we  deem  it  necessary 
to  describe  particularly  those  adjustments  which  are  most 
likely  to  need  attention. 

The  principal  adjustments  of  the  Transit  are  : The 

Levels. — The  Line  of  Collimation. — The  Standards. 

To  adjust  the  Levels:  Set  up  the  instrument  upon  its 

tripod  as  nearly  level  as  may  be,  and  having  unclamped 
the  plates,  bring  the  two  levels  above,  and 
he  on  a line  with,  the  two  pairs  of  leveling- 

screws  ; then  with  the  thumb  and  first  finger  of  each  hand 
clasp  the  heads  of  two  opposite  screws,  and,  turning  both 
thumbs  in  or  out,  as  may  be  needed,  bring  the  bubble  of 
the  level  directly  over  the  screws,  exactly  to  the  middle  of 
the  opening.  Without  moving  the  instrument,  proceed  in 
the  same  manner  to  bring  the  other  bubble  to  the  middle  ; 
after  doing  this  the  level  first  corrected  may  be  thrown  a 
little  out  ; bring  it  in  again  ; and  when  both  are  in  place 
turn  the  instrument  half-way  around  ; if  the  bubbles  are 


20 


TRA  NSIT-INSTR  UMEXTS. 


both  in  the  middle,  they  need  no  correction  ; but  if  not, 
with  the  adjusting-pin  turn  the  small  nuts  at  the  end  of 
the  levels  until  the  bubbles  are  moved  over  half  the  error  ; 
then  bring  the  bubbles  again  into  the  middle  by  the  level- 
ing-screws ; and  repeat  the  operation  until  the  bubbles  will 
remain  in  the  middle  during  a complete  revolution  of  the 
instrument,  when  the  adjustment  will  be  complete. 

To  adjust  the  Line  of  Collimation  : This  adjustment  is 

line  of  to  bring  the  cross-wires  into  such  a posi- 
colli M ation . tion  that  the  instrument,  when  placed  in 
the  middle  of  a straight  line,  will,  by  the  transit  of  the 
telescope,  cut  the  extremities  of  the  line.  Then,  having 
the  instrument  leveled,  determine  if  the  vertical  wire  is 
plumb,  by  focusing  on  a defined  point  and  observing  if  the 
wire  remains  on  that  point  when  the  telescope  is  elevated 
or  depressed.  If  not,  loosen  the  cross-wire  screws  and  by 
their  heads  turn  the  ring  until  correct.  Then  direct  the 
intersection  of  the  cross-wires  on  an  object  two  or  three 
hundred  feet  distant.  Set  the  clamps  and  transit  to  an 
object  found  or  placed  about  the  same  distance  in  the 
opposite  direction.  Unclamp,  and  turn  the  plates  half  way 
around  and  direct  again  to  the  first  object  and  then  transit 
to  the  second  object.  If  it  strikes  the  same  place  the  ad- 
justment is  correct. 

If  not,  however,  the  space  which  separates  the  wires 
from  the  second  point  observed  will  be  double  the  devia- 
tion of  that  point  from  a true  straight  line,  which  may  be 
conceived  as  drawn  through  the  first  point  and  the  center 
of  the  instrument,  since  the  error  is  the  result  of  two  obser- 
vations made  with  the  wires  when  they  are  out  of  the 
optical  axis  of  the  telescope. 

In  the  cut  on  page  21,  let  A represent  the  center  of 
the  instrument,  and  B C the  imaginary  straight  line,  upon 


TRA  NSIT-INSTR  UMENTS. 


21 


the  extremities  of  which  the  line  of  collimation  is  to  be 
adjusted. 

B represents  the  object  first  selected,  and  D the  point 
which  the  wires  bisected  when  the  telescope  was  reversed. 


When  the  instrument  is  turned  half  around,  and  the 
telescope  again  directed  to  B,  and  once  more  reversed,  the 
wires  will  bisect  an  object,  E,  situated  as  far  to  one  side  of 
the  true  line  as  the  point,  D,  is  on  the  other  side.  The 
space,  D E,  is  therefore  the  sum  of  two  deviations  of  the 
wires  from  a true  straight  line,  and  the  error  is  made  very 
apparent. 

In  order  to  correct  it,  use  the  two  capstan-head  screws 
on  the  sides  of  the  telescope,  these  being  the  ones  which 
affect  the  position  of  the  vertical  wire. 

Remember  that  the  eyepiece  inverts  the  position  of  the 
wires,  and  therefore  that  in  loosening  one  of  the  screws 
and  tightening  the  other  on  the  opposite  side,  the  operator 
must  proceed  as  if  to  increase  the  error  observed. 

The  wires  being  adjusted,  their  intersection  may  now  be 
brought  into  the  center  of  the  field  of  view  by  moving  the 
screws,  A A,  shown  in  the  sectional  view  of  the  telescope, 
page  7,  which  are  slackened  and  tightened  in  pairs,  the 
movement  being  now  direct,  until  the  wires  are  seen  in  their 
proper  position. 

It  is  here  proper  to  observe  that  the  position  of  the  line  of 
collimation  depends  upon  that  of  the  objective  solely,  so  that 
the  eyepiece  may,  as  in  the  case  just  described,  be  moved  in 
any  direction,  or  even  entirely  removed  and  a new  one  substi- 


D 


B 


E 


22 


TRA  NS  I T-INS  TR  UMENTS. 


tuted,  without  at  all  deranging  the  adjustment  of  the 
wires. 

To  adjust  the  Standards  : In  order  that  the  point  of  in- 

tersection  of  the  wires  may  trace  a vertical 

STANDARDS. 

line  as  the  telescope  is  directed  up  or  down, 
it  is  necessary  that  both  the  standards  of  the  telescope 
should  be  of  precisely  the  same  height.  To  ascertain  this, 
and  make  the  correction,  if  needed,  proceed  as  follows  : 

Having  the  line  of  collimation  previously  adjusted,  set 
up  the  instrument  in  a position  where  points  of  observation, 
such  as  the  point  and  base  of  a lofty  spire,  can  be  selected, 
giving  a long  range  in  a vertical  direction. 

Level  the  instrument,  direct  the  telescope  to  the  top  of 
the  object,  and  clamp  to  the  spindle  ; then  bring  the  tele- 
scope down  until  the  wires  bisect  some  good  point,  either 
found  or  marked  at  the  base  ; turn  the  instrument  half 
around,  direct  the  telescope  to  the  lower  point,  clamp  to 
the  spindle,  and  raise  the  telescope  to  the  highest  point.  If 
the  wires  bisect  it,  the  vertical  adjustment  is  effected  ; if 
they  are  thrown  to  either  side,  this  proves  that  the  standard 
opposite  to  that  side  is  the  highest,  the  apparent  error  being 
double  that  actually  due  to  this  cause.  To  correct  it,  we 
make  one  of  the  bearings  of  the  axis  movable,  so  that  by 
turning  a screw  underneath  this  sliding  piece,  as  well  as  the 
screws  which  fasten  the  cap  of  the  standard,  the  adjustment 
is  made  with  the  utmost  precision.  This  arrangement, 
which  is  common  to  all  of  our  Transits,  is  very  substantial 
and  easily  managed. 

Besides  the  three  adjustments  already  described,  which 
are  all  that  the  surveyor  will  ordinarily  be  required  to 
make,  there  are  other  adjustments  of  the  Transits  which  may 
sometimes-  be  required. 

To  adjust  the  Object-glass  Slide  : Having  set  up  and 


TRANSIT-INS  TR  UMENTS. 


23 


leveled  the  instrument,  the  line  of  collimation  being  also 
object-glass  adjusted  for  objects  from  three  hundred 
slide.  to  five  hundred  feet  distant,  clamp  the 
plates,  and  fix  the  vertical  cross-wire  upon  an  object  as 
distant  as  may  be  distinctly  seen  ; then,  without  disturbing 
the  instrument,  move  out  the  object-glass  so  as  to  bring  the 
vertical  wire  upon  an  object  as  near  as  the  range  of  the 
telescope  will  allow.  Having  this  clearly  in  mind,  loosen 
the  upper  clamp,  turn  the  instrument  half-way  around,  re- 
verse the  telescope,  clamp  the  instrument,  and  with  the 
tangent  screw  bring  the  vertical  wire  again  upon  the  near 
object;  then  draw  in  the  objective  until  the  distant  object 
first  sighted  upon  is  brought  into  distinct  vision.  If  the 
vertical  wire  strikes  the  same  line  as  at  first,  the  slide  is 
correct  for  both  near  and  remote  objects  and,  being  itself 
straight,  for  all  distances. 

But,  if  there  is  an  error,  proceed  as  follows  : First,  with 

the  thumb  and  forefinger  twist  off  the  thin  brass  tube  which 
covers  the  screws,  C C (see  page  7).  Next,  with  the  screw- 
driver, turn  the  two  screws,  C C,  on  the  opposite  sides  of  the 
telescope,  loosening  one  and  tightening  the  other  so  as  to  ap- 
parently increase  the  error,  making,  by  estimation,  one-half 
the  correction  required.  Then  go  over  the  usual  adjustment 
of  the  line  of  collimation  and,  having  it  completed,  repeat 
the  operation  above  described,  first  sighting  upon  the  distant 
object,  then  finding  a near  one  in  line,  and  then  reversing, 
making  correction,  etc.,  until  the  adjustment  is  complete. 

This  adjustment  is  always  made  by  us  before  the  instru- 
ment is  shipped,  is  peculiar  to  our  Transits,  and,  in  our 
experience,  furnishes  the  only  way  in  which  the  line  of 
collimation  can  be  made  correct  for  all  distances. 

The  adjustments  of  the  vertical  circle  and  the  level  on 
telescope  are  described  on  pages  49-54. 


THE  ENGINEERS’  TRANSIT. 


HE  LEVELING-HEAD  of  the  Engineers’  Transit  is 


A secured  to  the  sockets  by  a screw  and  washer  below  ; 
it  can  be  removed  for  cleaning  and  oiling,  but  should  be  in 
place  when  the  instrument  is  in  use  or  packed  for  transpor- 


The circular  plates,  with  their  accompanying  sockets,  are 
shown  in  section  on  page  15.  The  upper  plate,  A A,  carry- 
ing the  compass-circle  is  screwed  fast  to  the  flange  of  the 
interior  spindle  ; the  lower  plate  or  divided  limb,  B,  is 
fastened  to  the  exterior  socket,  C,  which  again  is  fitted  to 
and  turns  in  the  hollow  socket  of  the  leveling-head. 

To  take  apart  the  Engineers’  Transit : When  it  is 

necessary  to  separate  the  plates  of  the  Transit,  the  en- 
gineer should  proceed  as  follows  : 

(1)  Remove  the  screw  and  washer  underneath  which 
secure  the  leveling-head  to  the  sockets. 

(2)  Unscrew  the  nut  which  confines  the  spring  in  the 
thimble  opposed  to  the  tangent  screw  on  the  upper  plate. 

(3)  Take  out  the  three  small  screws  which  attach  the 
tangent  fixture  to  the  upper  plate.  The  plates  can  then  be 
readily  separated.  To  put  the  Transit  together  again,  pro- 
ceed exactly  the  reverse  of  the  operation  thus  described. 

The  engraving,  page  26,  shows  some  of  the  attach- 
ments often  used  with  the  Engineers’  Transit ; the  vertical 

ATTACHMENTS  arc>  ^eve^  on  telesC0Pe>  and  clamp  and 
TO  transits,  tangent  to  telescope  axis  with  gradienter 
screw.  These  and  other  appliances  are  used  where  level- 
ing, taking  vertical  angles,  etc.,  must  be  done  in  connection 


tation. 


25 


Engineers’  Transit,  two  verniers  to  limb,  5-inch  needle,  with  6-inch  vertical  arc  and  ver- 
nier moved  by  tangent  screw  and  reading  to  30  seconds,  level  on  telescope, 
gradienter  combined  with  clamp  and  tangent,  and  tripod. 

Price  as  shown,  $198.00. 


ENGINEERS'  TRANSIT. 


27 


with  the  ordinary  work  of  the  Transit,  and  the  attachments 
and  their  adjustments  are  described  on  pages  48-69. 

We  make  three  sizes  of  the  Engineers’  Transit,  having 
sizes  respectively  four,  four  and  one-half,  and 
and  weights,  five-inch  needles;  the  average  weight  of 
each  size,  with  plain  telescope,  is  as  follows  : 


4- inch  needle,  about 12J  lbs. 

4J-inch  needle,  about 14  lbs. 

5- inch  needle,  about 16  lbs. 


The  tripod  furnished  with  this  Transit  weighs  between 
nine  and  ten  pounds. 

ENGINEERS'  TRANSIT  WITH  SOLAR  ATTACHMENT. 

The  engraving  on  page  28  represents  our  Engineers’ 
Transit  with  five-inch  needle  and  attachments  of  vertical 
arc  of  three  inches  radius,  divided  on  silver  and  reading  to 
thirty  seconds,  level  on  telescope,  clamp  and  tangent  to 
telescope  axis,  and  Solar  apparatus  with  declination  arc 
reading  to  thirty  seconds. 

The  horizontal  limb  is  divided  on  sterling  silver,  and 
reads  to  single  minutes. 

The  compass-circle  is  also  made  movable  with  rack  and 
pinion,  for  setting  off  the  variation  of  the  needle. 

This  variation  arc  is  applied  to  Engineers’  Transits  of 
our  make,  at  an  extra  cost  of  $4.00  if  requested  when 
ordering  the  instrument. 

Where  the  variation  arc  is  desired  with  the  addition  of 
the  new  Solar  Attachment  to  any  Engineers’  Transit  sent 
to  us  for  the  purpose,  a charge  of  $15.00  will  be  made. 


28 


ENGINEERS’  TRANSIT,  WITH  SOLAR  ATTACHMENT. 
Price,  as  shown,  §250.00. 


LIGHT  MOUNTAIN  TRANSIT. 


"THIS  instrument,  shown  on  page  30,  is  a modification  of 
A the  Engineers’  Transit,  designed  for  mountain  and 
mine  surveys,  but  applicable  as  well  to  all  other  work  of 
the  engineer.  It  is  exceedingly  light  and  portable,  its 
needle  is  four  indies  long,  and  its  telescope  is  eight  inches 
long  with  a power  of  twenty  diameters. 

The  Sockets  are  like  those  shown  on  page  15  ; the  com- 
pass-circle is  movable  about  its  center,  so  as 

SOCKETS 

to  set  off  the  variation  of  the  needle. 

As  in  our  other  Transits,  the  limb  is  graduated  on  sterl- 
ing silver,  reading  usually  to  single  minutes  ; but,  if  desired, 
it  can  be  graduated  to  read  to  twenty  or  thirty  seconds. 

There  are  caps  above  the  leveling-screws  to  exclude 
dust,  as  in  our  other  instruments. 

The  cut  shows  the  celluloid  reflectors,  which  are  placed 
over  the  two  opposite  verniers  of  the  limb,  and  are  of 
special  value  in  the  surveys  of  mines,  to  throw  light  upon 
the  divisions  below. 

Like  the  Engineers’  Transit,  the  Mountain  Transit  is 
ATTACHMENTS  sometimes  used  with  a plain  telescope; 
for  transits,  but  oftener  with  one  or  more  extras,  as 
level,  clamp  and  tangent  and  vertical  arc,  as  shown. 

Frequently,  however,  the  Mountain  Transit  is  furnished 
as  shown  on  page  31,  with  vertical  arc,  level,  clamp  and 
tangent,  and  the  Solar  Attachment. 

The  Light  Mountain  Transit  is  almost  always  used  upon 
our  improved  extension  tripod  (see  page  179),  the  legs 

29 


30 


MOUNTAIN  TRANSIT. 


NO.  28. 

Light  Mountain  Transit,  two  verniers  to  limb,  4-inch  needle,  with  vertical  arc,  level  on 
telescope,  and  clamp  and  tangent  to  telescope  axis,  and  extension  tripod. 

Price,  $186.00. 


MOUNTAIN  TRANSIT. 


31 


NO.  30. 

Light  Mountain  Transit,  two  verniers  to  limb,  4-inch  needle,  with  solar  attachment, 
vertical  arc  reading  to  1 minute,  level  on  telescope,  and  clamp  and  tangent 
to  telescope  axis,  and  extension  tripod.  Price,  $245. 00. 


32 


MOUNTAIN  TRANSIT. 


of  which  can  be  lengthened  or  shortened  at  will.  It  is  thus 
adapted  for  use  in  mountain  surveys,  where  one  or  more 
legs  must  be  shortened  ; or  for  mines,  where  in  many  places 
a short  tripod  is  indispensable. 

If  desired,  the  sliding  pieces  can  be  easily  turned  end 
for  end,  the  points  being  thus  put  out  of  the  way  and  the 
tripod  more  easily  transported.  The  tripod  when  closed  is 
only  three  feet  long,  and  is  carried  by  a shawl  strap,  which 
we  furnish  with  it. 

The  Light  Mountain  Transit,  introduced  by  us  in  1876 
to  meet  a demand  for  a light  instrument  of  the  finest  qual- 
ity, has  met  with  a very  large  sale,  and  has  been  universally 
approved. 

While  it  is  a Transit  of  first  quality,  adapted  to  all 
kinds  of  work  which  may  be  required,  it  is  especially  fitted 
for  mining  or  mountain  surveying  where  great  portability 
is  desired. 

Besides  the  light  mahogany  box,  in  which  the  instru- 
* ment  is  packed  as  usual,  there  is  also  sup- 
leather  case.  pijecj  a light  sole-leather  case,  furnished 
with  shoulder-straps. 

The  weight  of  this  instrument  with  plain  telescope  and 
without  tripod  is  ten  pounds ; with  Solar  Attachment,  arc, 
level  and  clamp,  as  shown  in  the  cut,  twelve 

weight.  p0un(js  The  extension  tripod-weighs  about 

eight  and  one-half  pounds. 


THE  SURVEYORS’  TRANSIT. 


rFHE  Surveyors’  Transit  with  two  verniers  to  limb  has 
A essentially  the  same  construction  as  the  Engineers’ 
Transit,  but  its  compass-circle  is  movable  about  its  center, 
like  that  of  the  Mountain  Transit,  in  order  that  the  varia- 
tion of  the  needle  may  be  set  off  in  the  surveys  of  old  lines, 
or  in  running  lines  by  the  true  meridian. 

The  arrangement  of  the  sockets  and  leveling-head, 
however,  permits  the  Surveyors’  Transit  to  be 

SOCKETS 

detached  from  the  leveling-head  and  replaced 
upon  its  spindle,  when  desired,  without  in  any  way  disturb- 
ing its  adjustments. 

The  sectional  view,  page  35,  shows  the  interior  con- 
struction of  the  sockets  of  the  Transit,  the  manner  in 
which  it  is  detached  from  its  spindle,  and  the  means  by 
which  it  can  be  taken  apart  if  desired. 

In  the  figure,  the  limb,  B,  is  attached  to  the  main  socket, 
horizontal  C,  which  is  itself  carefully  fitted  to  the  con- 
limb.  ical  spindle,  H,  and  held  in  place  by  the 
spring-catch,  S. 

The  upper  plate,  A,  carrying  the  compass-circle,  stand- 
ards, etc.,  is  fastened  to  the  flanges  of  the  socket,  K,  which 
is  fitted  to  the  upper  conical  surface  of  the  main  socket,  C ; 
the  weight  of  all  the  parts  being  supported  on  the  small 
bearings  of  the  end  of  the  socket,  as  shown,  so  as  to  turn 
with  the  least  possible  friction. 

A small  conical  center,  in  which  a strong  screw  is 
inserted  from  below,  is  brought  down  firmly  upon  the 
upper  end  of  the  main  socket,  C,  thus  holding  the  two 

33 


Surveyor’s  Transit  two  verniers  to  limb,  6-inch  needle,  with  4%-inch  vertical  circle  and 
Surveyor  minute>  level  on  telescope  clamp  and  tangent  to  telescope 

axis,  and  tripod.  Price,  1160.00. 


SURVEYORS'  TRANSIT. 


35 


plates  of  the  instrument  securely  together,  and  at  the 
same  time  allowing  them  to  move  freely  around  each  other 
in  use. 

A disk  above  the  conical  center  contains  the  steel  center- 
pin  upon  which  rests  the  needle,  as  shown  ; the  disk  is 
fastened  to  the  upper  plate  by  two  screws. 

The  clamp  to  limb,  with  clamp-screw,  is  also  shown 
at  D F,  attached  to  the  main  socket  below. 

The  main  socket  with  all  its  parts  is  of  the  best  bell- 
metal,  and  is  most  carefully  and  thoroughly  made,  the  long 
bearing  of  the  sockets  insuring  their  firm  and  easy  move- 
ment, while  at  the  same  time  they  are  entirely  out  of  reach 
of  dust,  or  other  source  of  wear. 

When  desired,  the  whole  upper  part  of  the  instrument 
may  be  taken  off  from  the  spindle  by  pulling  out  the  head 


36 


SURVEYORS  TRANSIT. 


of  the  spring-catch  at  S,  and  when  replaced  will  be  secured 
by  the  self-acting  spring  of  the  catch. 

The  figure  also  shows  the  covers  of  the  leveling-screws, 
the  shifting  center  of  the  lower  leveling-plate,  and  the 
screw  and  loop  for  the  attachment  of  the  plummet 


TO  TAKE  APART  THE  SURVEYORS'  TRANSIT. 

When  it  is  necessary  to  separate  the  plates  of  the 
Transit,  proceed  as  follows  (see  page  35): 

(1)  Remove  the  clamp-screw  of  the  variation  arc  and 
take  off  the  head  of  the  pinion,  both  outside  the  compass- 
circle.  (2)  Unscrew  the  bezel-ring  holding  the  glass 
cover  of  the  compass,  remove  the  needle  and  button  be- 
neath it,  and  take  out  the  two  screws,  so  as  to  remove  the 
disk.  (3)  Take  the  instrument  from  its  spindle,  and  with  a 
screw-driver  take  out  the  screw  from  the  under  side  of  the 
conical  center.  (4)  Drive  out  the  center  from  below  by  a 
round  piece  of  wood,  holding  the  instrument  so  that  the 
center  will  not  bruise  the  circle.  (5)  Set  the  instrument 
again  upon  its  spindle,  unscrew  the  milled  head  cap  from 
the  thimble  containing  the  opposing  spring  of  the  tangent 
movement  to  limb,  take  out  the  three  screws  which  fasten 
that  movement  to  the  upper  plate,  and  the  plates  can  then 
be  separated.  To  put  the  Transit  together  again,  proceed 
exactly  the  reverse  of  the  operation  thus  described. 

S1ZES  The  sizes  and  weights  of  the  Sur- 

and  weights,  veyors’  Transits  with  plain  telescope, and 
having  two  verniers  to  limb  are  : 

4- in.  needle,  with  leveling-head,  but  no  tripod,  about  13f  lbs. 

5- in.  needle,  “ “ “ “ “ “ 16^  lbs. 

6J-in.  needle,  “ “ “ “ “ “ 17J  lbs. 


SURVEYORS'  TRANSIT. 


37 


The  Surveyors’  Transit  with  one  vernier  to  limb  is  a 
modification  of  the  instrument  just  described,  in  which 
there  is  but  one  double  vernier  to  limb  and  a different 
arrangement  of  the  sockets,  as  shown  in  the  sectional  cut 
on  page  39. 

The  instrument  is  more  compact  and  somewhat  lighter 
than  that  with  two  verniers,  and  is  furnished  at  less  cost. 
Its  graduations,  telescope  and  attachments  are  all  equal  to 
those  of  the  best  Transits  ; and  after  an  experience  of  more 
than  thirty  years  the  instrument  has  proved  itself  in  every 
way  satisfactory  for  all  classes  of  work. 

This  instrument  may  be  taken  apart  by  first  removing 
the  pinion  head  and  clamp-screw  near  the  compass-circle, 
then  unscrewing  the  bezel-ring,  taking  out  the  needle  and 
button  underneath,  and  next  removing  the  disk  in  which 
the  center-pin  is  fixed,  by  taking  out  two  small  screws 
which  confine  it.  The.  four  screws  which  hold  the  washer 
to  the  under  plate  must  then  be  removed,  the  milled  head 
cap,  of  the  tangent  opposing  spring  be  unscrewed,  and  the 
three  screws  which  secure  the  tangent  support  to  the  upper 
plate  removed  ; and  then  the  plates  can  be  separated.  The 
several  parts  are  replaced  in  the  reverse  order. 

The  adjustments  and  use  of  this  instrument  are  like 
those  of  the  others  already  described,  and  its  attachments 
to  the  telescope  the  same,  if  desired. 

It  is  represented  in  the  cut  with  a level  on  telescope  and 
clamp  and  tangent  to  telescope  axis.  (See  page  38.) 

The  sectional  cut,  on  page  39,  shows  the  arrangement 
the  of  sockets  of  this  instrument.  The  spin- 
sockets.  die,  C,  is  fitted  to  the  socket  of  the  leveling- 
head,  as  shown,  and  connected  therewith  by  a screw  and 
washer  underneath,  as  in  the  figure. 


Surveyors'  Transit,  one  vernier  to  limb,  5-inch  needle,  with  level  on  telescope,  clamp 
and  tangent  to  telescope  axis,  and  tripod. 

Price,  §133:00. 


SURVEYORS'  TRANSIT. 


39 


The  socket,  K,  is  formed  in  the  metal  of  the  upper  plate, 
a strong  washer  with  four  screws,  only  two  of  which  are 
seen  in  the  cut,  keeping  the  two  plates  -together,  but  at  the 
same  time  allowing  them  to  turn  freely  around  each  other. 

The  clamp  to  limb,  with  clamp-screw,  is  shown  in 
dotted  lines  at  D F,  under  the  plates. 

The  vernier  with  the  opening  above  is  shown  on  the  left 
at  A.  The  arrangement  of  the  center-pin,  needle,  etc.,  is 
like  that^of  the  Transit  with  two  verniers,  but  the  instru- 
ment remains  attached  to  the  leveling-head  like  the  En- 
gineers’ Transit. 


THE  SOCKETS  AND  CIRCULAR  PLATES. 


sizes  The  sizes  and  weights  of  the  Surveyors’ 

and  weights.  Transits  with  plain  telescope,  and  having 
one  vernier  to  limb  are  : 


4- in  needle,  with  leveling-head,  but  no  tripod,  about  13  lbs. 

5- in  needle,  “ “ “ “ “ “ 16  lbs. 

5J-in.  needle,  “ “ “ “ 6i  17  lbs. 


40 


SURVEYORS'  TRANSIT. 


SURVEYORS'  TRANSIT  WITH  SOLAR  ATTACH- 
MENT. 

The  engraving  on  page  41  represents  our  Surveyors' 
Transit  with  five-inch  needle,  to  which  is  adapted  the  Solar 
Attachment  with  vertical  arc,  level  on  telescope,  and  clamp 
and  tangent  to  axis  of  telescope  ; both  the  vertical  arc  and 
the  arc  of  the  declination  arm  being  graduated  on  silver 
andTeading  by  vernier  to  thirty  seconds. 

The  instrument  is  furnished  with  two  verniers  to  limb 
or  with  one  vernier  to  limb,  as  may  be  desired  ; both  pat- 
terns have  shifting  center  to  the  tripod  head. 

PRICES. 

No.  Price. 

60.  Surveyors’  Transit,  two  verniers  to  limb,  5-inch  needle, 
with  Solar  Attachment,  vertical  arc  of  3 inches  radius, 
level  on  telescope,  clamp  and  tangent  to  telescope  axis, 

and  tripod $226.00 

90.  Surveyors’  Transit,  one  vernier  to  limb,  5-inch  needle, 
with  Solar  Attachment,  vertical  arc  of  3 inches  radius, 
level  on  telescope,  clamp  and  tangent  to  telescope  axis, 
and  tripod 


211.00 


THE  RECONNOISSANCE  TRANSIT. 


TN  RESPONSE  to  a demand  for  a very  light  Transit  for 
A rapid  work,  where  extreme  accuracy  is  not  required, 
we  have  introduced  the  Reconnoissance  Transit,  shown  on 
page  43. 

It  has  a needle  three  and  one-half  inches  in  length,  a 
limb  five  inches  in  diameter,  graduated  on  sterling  silver, 
reading  by  one  double  vernier  to  single  minutes,  and  is  pro- 
vided with  a spring  tangent  movement  like  the  larger  in- 
struments. 

The  limb  is  figured  from  0 to  180  unless  otherwise 
ordered. 

The  telescope  is  nine  inches  long  and  has  a power  of 
from  eighteen  to  twenty  diameters,  and  is  furnished  with 
stadia  wires  for  measuring  distances  ; it  has  also  a long 
level,  vertical  circle  reading  to  five  minutes,  and  clamp  and 
tangent  to  axis.  The  object-glass  is  focused  by  a rack  and 
pinfon  and  the  eyepiece  by  a spiral  movement. 

The  compass-circle  is  arranged  to  set  off  the  variation 
of  the  needle,  the  movement  being  made  by  a pinion. 

The  instrument  has  also,  as  shown,  a leveling-head  with 
shifting  center,  and  with  spring  clamp  and  tangent,  and  it 
is  set  upon  our  light  extension  tripod,  the  legs  of  which 
close  up  to  about  three  feet  in  length. 

This  instrument  is  finished  with  the  same  care  as  our 
larger  and  more  expensive  Transits,  and  we  recommend  it 
as  a thoroughly  well  made  and  reliable  instrument  for  a 
large  variety  of  work.  The  quality  of  the  instrument, 
together  with  its  portability,  have  already  made  it  very 
popular. 

The  weight  of  this  Transit  without  the  tripod  is  about 
seven  and  three-quarter  pounds,  complete  with  tripod  about 
fifteen  pounds. 


42 


RECONNOISSA NCE  TRANSIT. 


43 


No.  IVIO.  100.  . Price. 

100.  Reconnoissance  Transit,  one  vernier  to  limb,  3 J-inch  needle, 
with  3 J -inch  vertical  circle  and  vernier  reading  to  five 
minutes,  level  on  telescope,  clamp  and  tangent  to  tele- 
scope axis,  and  leveling  tripod  with  extension  legs $115.00 

102.  Reconnoissance  Transit,  same  as  No.  100,  but  with  4J-inch 

vertical  circle  and  vernier  reading  to  one  minute 122.00 


THE  BUILDERS’  TRANSIT. 

* 1 'HE  Builders'  Transit,  see  page  45,  is  an  instrument 
* devised  for  use  in  the  construction  of  buildings  where 
it  is  necessary  not  only  to  furnish  levels,  but  to  determine 
points  in  a vertical  plane  above  or  below  the  level  line,  or 
on  either  side  and  in  line  with  the  center  of  the  instrument, 
more  conveniently  than  can  be  done  with  the  Architects’ 
Level.  The  instrument  has  a telescope  with  long  gradu- 
ated level,  clamp  and  tangent  to  axis,  a graduated  limb 
reading  by  an  index  to  one  degree,  clamp  and  tangent  to 
both  limb  and  leveling-head,  a shifting  center,  plain  tripod 
and  trivet-plate. 

In  use,  the  instrument  is  set  up  either  upon  the  tripod 
or  trivet,  and  the  plates  are  accurately  leveled  by  the  two 
levels  shown. 

If  it  is  desired  to  run  a level  line,  the  bubble  of  the  tel- 
escope level  is  brought  into  the  middle  by  the  clamp  and 
tangent  of  the  axis,  in  which  position  the 
level  line.  horizontal  wire  of  the  telescope  will  deter- 
mine a level  line,  as  in  the  telescope  of  the  ordinary  Level, 
and  any  horizontal  angle  to  one  degree  may  be  read  off 
upon  the  limb.  The  limb  is  figured  from  0 to  180  each  way. 

When  necessary  to  obtain  points  in  a vertical  plane, 
either  above  or  below  a given  point,  the 
vertical  line.  pjates  should  be  clamped  and  the  clamp 

of  the  telescope  axis  released,  when  the  telescope  may  be 
directed  either  above  or  below  to  the  point  desired. 

To  determine  two  points  in  a straight  line  with  the  in- 
strument and  on  opposite  sides  of  its 
straight  line.  center^  direct  the  telescope  to  one  of  the 

points,  then  clamp  the  plates,  and  the  other  point  may  be 
obtained  by  reversing  the  telescope  upon  its  axis, 

44 


BUILDERS'  TRANSIT. 


45 


The  weight  of  the  Builders’  Transit  is  about  seven 
pounds ; and  with  the  tripod  complete  about  thirteen 
pounds. 


NO.  105. 

Builders’  Transit,  with  level  on  telescope,  clamp  and  tangent  to  telescope  axis,  limb  and 
spindle,  and  with  leveling-screws  and  tripod,  as  shown. 

Price,  $80.00. 


THE  VERNIER  TRANSIT-COMPASS. 


HIS  instrument,  shown  on  page  47,  is  essentially  a 


Vernier  Compass  with  a telescope  in  place  of  the 
ordinary  sight-vanes,  thus  giving  the  surveyor  the  means 
of  taking  long  sights,  either  on  a level  or  on  hilly  ground, 
with  ease  and  accuracy. 

The  telescope  can  also  be  supplied  with  attachments, 
as  shown,  and  levels  and  angles  of  elevation  and  depression 
taken,  as  with  the  more  expensive  instruments. 

The  telescope  is  eleven  inches  long  and  of  fine  quality. 

The  compass-circle  is  moved  about  its  center  by  a pin- 
ion placed  underneath  the  circular  plate,  and  the  variation 
of  the  needle  is  set  off  to  single  minutes  upon  a graduated 
arc  attached  to  the  plate,  as  shown  in  the  cut.  There  is 
also  a clamp-screw  by  which  the  circle  is  made  secure. 

The  figure  represents  the  instrument  with  six-inch 
needle  ; in  the  smaller  size  the  vernier  of  the  compass- 
circle  is  within  the  box  and  under  the  glass,  as  in  the  Sur- 
veyors’ Transit. 

The  needle-lifting  screw  is  also  underneath  the  plate, 
but  is  not  shown  in  the  cut. 

The  clamp-screw,  by  which  the  instrument  is  fixed  to 
the  spindle,  and  the  spring-catch  which  secures  it,  are  both 
shown  on  opposite  sides  of  the  socket. 

The  levels  are  both  above  the  plate,  and  are  made  ad- 
justable by  capstan-head  nuts  at  either  end. 

This  instrument  is  commonly  used  on  a ball-spindle 
placed  in  a compass  tripod,  as  shown  on  page  47,  but  it  is 
sometimes  fitted  to  a leveling-head  like  that  shown  on 
page  123. 


46 


VERNIER  TRANSIT -COMPASS. 


47 


sizes  We  make  two  sizes  of  this  instrument, 

AND  WEIGHTS,  having  respectively  five  and  six-inch 
needles,  the  average  weights  of  which  are  as  follows  : 

5- inch  needle,  plain  telescope,  and  without  tripod,  9 lbs. 

6- inch  needle,  “ “ “ “ <<  lia.  ]bs> 


Vernier  Transit,  6-inch  needle,  with  3%-inch  vertical  circle  and  vernier  reading  to  6 
minutes,  level  on  telescope,  clamp  and  tangent  to  telescope  axis,  and  tripod. 

Price,  $101. 00. 


ATTACHMENTS  FOR  TRANSITS. 


IN  THE  use  of  the  Transit  it  is  generally  found  advis- 
able to  add  one  or  more  attachments  to  the  telescope. 
All  our  Transits  and  their  attachments  are  now  made  to 
standard  sizes,  so  that  one  or  more  of  these  useful  appli- 
ances can  be  fitted  to  the  instrument  at  any  time  without 
additional  expense  other  than  the  cost  of  the  attachment 
itself. 

When  any  of  these  attachments  are  desired,  either  for 
our  instruments  or  those  of  other  makers,  it  is  best  to  send 
the  instrument  to  us  ; in  some  cases  they  can  be  applied 
by  a skilful  mechanic  nearer  the  customer,  but  this  is  gen- 
erally more  expensive  and  less  satisfactory. 

The  principal  attachments  for  the  Transit  are : 

Vertical  Circle  (see  pages  49-51). 

Vertical  Arc  (see  page  52). 

Level  on  Telescope  (see  page  53). 

Clamp  and  Tangent  to  Telescope  Axis  (see  pages  53  and  55). 
Sights  on  Telescope  (see  page  55). 

Sights  on  Standards  for  Right  Angle  Observation  (see  page  55). 
Attached  Magnifiers  to  Horizontal  Limb  (see  page  55). 
Gradienter,  combined  with  Clamp  and  Tangent  (see  page  56). 
Detachable  Telescopes  for  Vertical  Sighting  (see  page  58). 
Reflector  for  Illuminating  the  Cross- Wires  (see  page  59). 
Diagonal  Prism  for  Eyepiece  of  Telescope  (see  page  59). 
Plummet-Lamp  (see  page  60). 

Solar  Attachment  to  Telescope  (see  pages  61-69). 

Solar  Screen  (see  page  80). 


48 


ATTACHMENTS  FOR  TRANSITS. 


49 


THE  VERTICAL  CIRCLE. 


NO.  136. 


The  Vertical  Circle  has  its  divisions  on  sterling  silver 
and  is  figured  from  0 to  90  ; two  sizes  are  most  commonly 
used,  the  three  and  one-half-inch  circle  reading  by  vernier 
to  five  minutes,  as  shown  in  Fig.  117,  and  the  four  and  one- 
half-inch  circle  reading  by  vernier  to  single  minutes,  as 
shown  in  Fig.  136. 

We  also  make  these  circles  five  inches  in  diameter  when 
desired,  reading  to  one  minute. 

To  adjust  the  Vertical  Circle  : Having  the  instrument 

firmly  set  up  and  carefully  leveled,  bring  into  line  the  zeros 
of  the  circle  and  vernier,  and  with  the  tele- 
adjustment.  SCOpe  some  well-defined  point,  from 

one  hundred  to  five  hundred  feet  distant,  which  is  cut  by 
the  horizontal  wire.  Turn  the  instrument  half-way  around, 
transit  the  telescope,  and  fixing  the  wire  upon  the  same 
point  as  before,  observe  if  the  zeros  are  again  in  line. 
If  not,  loosen  the  capstan-head  screws  which  fasten  the 


50  ATTACHMENTS  FOR  TRANSITS. 

vernier,  and  move  the  zero  of  the  vernier  over  half  the 
error  ; bring  the  zeros  again  into  coincidence,  and  proceed 
exactly  as  before,  until  the  error  is  entirely  corrected,  when 
the  adjustment  will  be  complete.  In  almost  all  cases  the 
error  is  slight,  and  may  be  most  readily  removed  by  putting 
the  zeros  in  line  and  then  moving  the  horizontal  wire  by  the 
vertical  capstan- head  screws  over  half  the  interval. 


The  engraving  shown  above  illustrates  an  aluminum 
guard  as  applied  to  the  vertical  circle  to  protect  the  gradua- 
tions from  injury.  The  extra  cost  for  this  attachment 
is  $6.00. 


PRICES. 

No. 

135.  3J-inch  Vertical  Circle $ 8.00 

136.  41-inch  “ “ 12.00 

137.  5 -inch  “ “ 15.00 

138.  5 -inch  “ “ with  two  opposite  double  verniers...  35.00 

Aluminum  Guard  for  Vertical  Circles,  extra 6.00 


ATTACHMENTS  FOR  TRANSITS. 


51 


NO.  138. 


We  also  make  a modification  of  the  five-inch  circle, 
shown  in  Fig.  138,  enclosed  in  outside  shield,  fastened  to 
which  are  two  opposite  verniers  reading  to  single  minutes, 
the  arm  projecting  from  the  lower  side  being  actuated  by 
capstan-head  screws,  as  shown  in  the  cut,  to  bring  the  zeros 
of  the  verniers  into  exact  adjustment  in  relation  to  the  level. 

The  price  of  Vertical  Circle,  No.  138,  is  $35.00. 


\ 


K 


52 


attachments  for  transits. 


THE  VERTICAL  ARC. 


NOS.  139  AND  140. 


The  Vertical  Arc  is  made  in  two  sizes,  two  and  one-half 
and  three  inches  radius,  graduated  on  sterling  silver  and  read 
by  a vernier  swung  from  the  axis  and  movable  by  a tangent 
screw. 

The  arc  is  movable  around  its  bearing  on  the  axis,  can 
be  readily  clamped  at  0 with  the  vernier  in  any  position  of 
the  telescope,  and  any  degree  of  elevation  can  be  read  off 
directly  on  the  arc. 

The  arc  of  two  and  one  -half  inches  radius  is  generally 
used  on  the  Light  Mountain  Transit,  and  reads  by  its  vernier 
to  single  minutes,  while  the  arc  of  three  inches  radius  is 
commonly  used  on  the  larger  Transits,  and  is  read  by  the 
vernier  to  thirty  seconds.  The  Vertical  Arc  can  be  readily 
added  to  any  Transit  of  our  manufacture. 

Price  of  the  Vertical  Arc,  either  size 


$18.00 


ATTACHMENTS  FOR  TRANSITS. 


53 


THE  LEVEL  ON  TELESCOPE,  AND  CLAMP  AND 
TANGENT  TO  TELESCOPE  AXIS. 


NOS.  145  AND  148. 


The  Level  on  Telescope,  No.  145,  consists  of  a brass  tube 
about  six  and  one -half  inches  long,  each  end  of  which  is 
held  between  two  capstan  nuts  connected  with  a screw  or 
stem  attached  to  the  under  side  of  the  telescope  tube. 

The  vial  enclosed  in  the  tube  is  a little  over  five  inches 
long  and  half  an  inch  in  diameter,  is  ground  on  its  interior 
surface  so  as  to  insure  an  even  and  sensitive  bubble,  the 
length  of  which  is  measured  by  the  scale  above ; the  scale 
is  divided  into  tenths  of  an  inch,  and  is  figured  from  0 at 
the  middle  to  5,  10,  15,  20  on  either  side,  and  thus  deter- 
mines when  the  bubble  is  brought  into  the  middle  of  its  run. 

Price  of  Level  on  Telescope  $12.00 

To  adjust  the  Level  on  Telescope  : When  the  vernier 

of  the  vertical  circle  is  adjusted  as  per 

ADJUSTMENT.  4^  and  jg  ^ zerQ,  the  pne  0f  C0Hi- 

mation  is  level  and  the  bubble  may  be  brought  into  the 


54 


ATTACHMENTS  FOR  TRANSITS. 


middle  of  its  run  by  the  capstan-head  nuts.  Another 
method  : First  level  the  instrument  carefully,  and  with 

the  clamp  and  tangent  movement  to  the  axis  make  the 
telescope  horizontal,  as  near  as  may  be,  by  the  eye  ; then, 
having  the  line  of  collimation  previously  adjusted,  drive  a 
stake  at  a convenient  distance,  say  from  one  hundred  to 
three  hundred  feet,  and  note  the  height  cut  by  the  hori- 
zontal wire  upon  a staff  set  at  the  top  of  the  stake. 

Fix  another  stake  in  the  opposite  direction  and  at  the 
same  distance  from  the  instrument,  and  without  disturbing 
the  telescope  turn  the  instrument  upon  its  spindle,  set  the 
staff  upon  the  stake,  and  drive  the  stake  into  the  ground 
until  the  same  height  is  indicated  as  in  the  first  observation. 

The  top  of  the  two  stakes  will  then  be  in  the  same  hori- 
zontal line,  however  much  the  telescope  may  be  out  of  level. 

Now  remove  the  instrument  from  fifty  to  one  hundred 
feet  to  one  side  of  either  of  the  stakes  and  in  line  with 
both;  again  level  the  instrument,  clamp  the  telescope  as 
nearly  horizontal  as  may  be,  and  note  the  heights  indicated 
upon  the  staff  placed  first  upon  the  nearest  and  then  upon 
the  most  distant  stake.  If  both  agree,  the  telescope  is 
level ; if  they  do  not  agree,  then  with  the  tangent  screw 
move  the  wire  over  nearly  the  whole  error,  as  shown  at  the 
distant  stake,  and  repeat  the  operation  just  described. 
Proceed  thus  until  the  horizontal  wire  will  indicate  the 
same  height  at  both  stakes,  when  the  telescope  will  be 
truly  horizontal.  Taking  care  not  to  disturb  the  position 
of  the  telescope,  bring  the  bubble  into  the  middle  by  the 
little  leveling-nuts  at  the  end  of  the  tube,  when  the  adjust- 
ment will  be  complete. 


ATTACHMENTS  FOR  TRANSITS . 


55 


THE  CLAMP  AND  TANGENT \ 

The  Clamp  and  Tangent,  No.  148,  consists  of  an  arm  at 
one  end  encircling  the  telescope  axis,  and  at  the  other  end 
connected  with  the  tangent  screw  ; the  clamp  is  fastened 
at  will  to  the  axis  by  a clamp-screw  inserted  at  one  side  of 
the  ring,  and  then  by  turning  the  tangent  screw  the  tele- 
scope is  raised  or  lowered  as  desired. 

The  clamp  and  tangent  must  always  accompany  the  ver- 
tical circle  and  level  on  telescope,  whenever  either  is  added 
to  a Transit.  Price,  $6.00. 

SIGHTS  ON  TELESCOPE  AND  ON  STANDARDS. 

For  convenience  of  observation  we  occasionally  place 
a pair  of  small  sights  on  the  telescopes  of  our  Transits. 
These  sights  have  folding  joints,  so  that  they  may  lie  close 
to  the  telescope  when  not  in  use.  Sights  are  also  placed 
on  the  standards  at  an  angle  of  ninety  degrees  with  the  tele- 
scope, for  use  in  offsetting. 

Price  of  either  style,  per  pair . $8.00 

Attached  Magnifiers  are  frequently  used  over  the  ver- 
niers of  the  horizontal  or  vertical  arc,  and  are  held  by  a 

universal  jointed  arm  which  allows  the 

MAGNIFIERS.  . , , , , 4 , , 

lens  to  be  placed  at  will  over  any  point  of 

the  vernier.  Price,  each,  $5.00. 


56 


ATTACHMENTS  TOR  TRANSITS . 


GR A DIENTER. 


GRADIENTER  ATTACHMENT.  Price,  $18.00. 

This  attachment,  as  shown,  is  often  used  with  the  Transit 
for  determining  distances,  fixing  grades,  and  similar  work. 

It  consists  mainly  of  a screw  attached  to  the  expanded 
arm  of  the  ordinary  clamp  of  the  telescope  axis  ; the  screw 
is  accurately  cut,  and  passing  through  a nut  in  one  side  of 
the  arm,  presses  against  a little  stud,  A,  fixed  to  the  inside 
surface  of  the  right-hand  standard.  In  the  side  of  the  arm 
opposite  the  screw  is  an  enclosed  spiral  spring  which 
presses  against  the  side  of  the  stud,  thus  securing  a positive 
movement  of  the  gradienter-screw. 


ATTACHMENTS  FOR  TRANSITS. 


57 


Near  the  other  end  of  the  sqrew,  and  turning  with  it,  is 
a wheel,  or  micrometer,  the  rim  of  which  is  covered  with 
sterling  silver,  and  divided  into  one  hundred  equal  parts. 

A small  silver  scale,  attached  to  the  arm  and  just  above 
the  micrometer  wheel,  is  divided  into  spaces,  each  of  which 
is  just  equal  to  one  revolution  'of  the  screw  ; so  that  by 
comparing  the  edge  of  the  wheel  with  the  divisions  of  the 
scale,  the  number  of  complete  revolutions  of  the  screw  can 
be  easily  counted. 

When  the  clamp  is  made  fast  to  the  axis  by  the  clamp- 
screw,  and  the  gradienter-screw  is  turned,  it  will  move  the 
measuring  telescope  vertically,  like  the  tangent  screw 
distances,  ordinarily  used.  And  as  the  value  of  the 
screw  thread  is  such  that  a complete  revolution  of  the  screw 
will  move  the  horizontal  cross-wire  of  the  telescope  over  a 
space  of  one  foot  on  a vertical  rod  at  a distance  of  one 
hundred  feet,  it  is  clear  that  when  the  screw  is  turned 
through  fifty  spaces  on  the  graduated  head,  the  wire  will 
pass  over  fifty  hundredths,  or  one-half  a foot  on  the  rod, 
and  so  on  in  the  same  proportion.  In  this  way  the  gra- 
dienter  can  be  used  in  the  measurement  of  distances. 

To  avoid  any  possibility  of  error,  it  is  advisable  that 
observations  should  not  be  taken  by  a reversal  of  the  screw. 

Grades  can  also  be  established  with  great  facility,  as  fol- 
lows: Level  the  instrument ; bring  the  telescope  level-bubble 
to  the  middle  by  the  clamp  and  gradienter-screw  ; move 
the  graduated  head  until  its  zero  is  brought  to 

GRADES  ° 

the  edge  of  the  scale  ; then  turn  off  as  many 
spaces  on  the  head  as  there  are  hundredths  of  feet  to  the 
hundred  in  the  grade  to  be  established. 


58 


ATTACHMENTS  EOT  TRANSITS, 


DETACHABLE  TELESCOPES  FOR  VERTICAL 
SIGHTING, 

A common  arrangement  for 
sighting  up  or  down  a vertical 
shaft  is  shown  in  No.  160,  in 
which  an  extra  telescope  is  fitted 
by  a flange  and  disk  connecting  it 
with  the  axis,  so  as 
to  make  it  precisely 
parallel  to  the  main 
telescope  ; a coun- 
terpoise, as  shown, 
is  fitted  to  the  other 
end,  and  both  can 
be  detached  at 
pleasure,  and  placed 
in  the  Transit  box 
when  not  in  use. 


NO.  160. 


NO.  161. 


In  No.  161,  the 
extra  telescope  is 
connected  with  the 
main  telescope  by 
coupling-nuts,  which 
fasten  it  securely 
directly  over  the 
center  of  the  instru- 
ment and  allow  its 
ready  removal  and  replacement 
without  disturbing  its  adjust- 
ments. It  will  be  understood 
that  in  both  arrangements  the 


ATTACHMENTS  FOR  TRANSITS. 


59 


extra  telescope  is  adjusted  to  the  main  telescope  of  the 
Transit  so  that  the  lines  of  collimation  of  both  are  parallel 
and  in  the  same  plane,  horizontal  in  No.  160  and  vertical  in 
No.  161  ; and  in  both  the  extra  telescope  swings  over  the 
outside  of  the  Transit  plates.  The  diagonal  prism  is  often 
used  with  the  extra  telescope  for  greater  convenience  in 
sighting. 

Price  of  either  Telescope,  No.  160  or  161 $25.00. 


NO.  165. 

REFLECTOR. 
Price,  $4.00. 


kn-rnmm 


The  Reflector,  No.  165,  is  an 
elliptical  piece  of  silver,  inclined  at 
an  angle  of  forty-five  degrees  with 
its  ring,  which  is  fitted  to  the 
object-glass  end  of  the  telescope. 
The  hole  in  the  Reflector  allows  the 
use  of  the  telescope,  while  a light 
held  near  the  inner  surface  illumi- 
nates the  cross-wires. 

The  Diagonal  Prism,  ’No.  168,  is 
used  when  greater  vertical  angles  are 
to  be  taken  than  are  possible  with  the 
ordinary  telescope.  It  consists  of  a 
prism  attached  to  the  cap  of  the  eye- 
piece, by  which  the  object  is  presented 
to  the  eye  when  placed  at  right  angles 
with  the  telescope.  When  the  telescope 
is  directed  to  the  sun  the  slide  or  darkener  containing 
colored  glass  is  moved  over  the  opening. 

The  circular  plate  with  which  the  prism  is  connected  is 
made  to  turn  in  the  cap,  so  that,  when  it  is  substituted  for 
the  ordinary  cap  of  the  eyepiece,  the  opening  of  the  prism 
can  be  easily  adjusted  to  the  position  of  the  eye.  Observa- 
tions can  be  taken  with  the  prism  up  to  an  angle  of  sixty 
degrees  elevation. 


NO.  168. 

DIAGONAL  PRISM. 
Price,  $8.00. 


60 


ATTACHMENTS  FOR  TRANSITS. 


NO.  170. 

PLUMMET-LAMP. 


The  Plummet-Lamp,  No.  170,  is  a 
large  plummet,  of  which  the  upper  part  is 
hollow  to  contain  oil  ; it  has  also  a tube 
for  a wick,  and  an  extinguisher. 

It  is  hung  in  gimbals  by  a chain  with 
hook,  and  so  always  assumes  a vertical 
position,  and  when  suspended  from  the 
shifting  center  of  a leveling-head  it  can  be 
easily  adjusted  over  a given  point. 

Two  of  these  lamps  are  often  packed 
in  a simple  wooden  case,  furnished  with 
a strap  to  sling  over  the  shoulders.  The 
weight  of  each  lamp  is  about  one  and  one- 
quarter  pounds,  and  the  price  of  each  as 
shown  is  $10.00. 


SOLAR  ATTACHMENT. 


NO.  190. 


'T'HE  Solar  Attachment  is  essentially  the  solar  appara- 
A tus  of  Burt  placed  upon  the  cross-bar  of  the  ordi- 
nary Transit.  A disk  one  and  one-half  inches  in  diam- 
eter, having  a short  round  pivot  projecting  above  its 
upper  surface,  is  first  securely  screwed  to  the  tele- 
scope axis.  Upon  this  pivot  rests  the  enlarged  base  of  the 
polar  axis,  which  is  also  firmly  connected  with  the  disk 

61 


62 


SOLAR  ATTACHMENT. 


y 


by  four  capstan-head  screws  passing  from  the  under  side  of 
the  disk  into  the  base  already  named.  These  screws  serve 
to  adjust  the  polar  axis,  as  will  be  explained  hereafter. 

The  Hour-Circle  surrounding  the  base  of  the  polar  axis 
is  easily  movable  about  it,  and  can  be  fastened  at  any 
point  desired  by  two  flat  head  screws 
hour-circle.  above  js  divided  to  five  minutes  of 
time,  is  figured  from  I to  XII,  and  is  read  by  an  index 
fixed  to  the  declination  arc  and  moving  with  it.  A hollow 
cone,  or  socket,  fitting  the  polar  axis  and  made  to  move 
upon  it,  or  to  be  clamped  at  any  point  desired  by  a milled 
head  screw  on  top,  furnishes  by  its  arms  below  a firm 
support  for  the  declination  arc,  which  is  securely  fastened 
to  it. 

The  Declination  Arc  has  a radius  of  about  five  inches, 
and  is  divided  to  quarter  degrees.  On  Mountain  Transits 
declination  ^ rea^s  by  its  vernier  to  single  minutes  of 
ARC-  arc,  and  on  the  larger  Transits  to  half  min- 

utes of  arc,  the  divisions  of  both  vernier  and  limb  being  in 
the  same  plane.  The  declination  arc  has  the  usual  lenses 
and  silver  plate  on  the  two  opposite  blocks,  also  a clamp 
and  tangent  movement,  as  shown  in  the  cut.  The  arc  of 
the  declination  limb  is  turned  on  its  axis  and  one  or  the 
other  solar  lens  used,  as  the  sun  is  north  or  south  of  the 
equator ; the  cut  shows  its  position  when  the  sun  is 
north. 

The  Latitude  is  set  off  by  means  of  a large  vertical 
limb  figured  from  the  center  each  way  in  two#  rows, 
LAT|TUDE  from  0 to  80°  and  from  90°  to  10°,  the  first 
ARC-  series  being  intended  for  reading  vertical  angles 
and  the  latter  series  for  setting  off  the  latitude.  The 
vernier  of  the  vertical  limb  is  made  movable  by  the 
tangent  screw  attached,  so  that  its  zero  and  that  of  the 


SOLAR  ATTACHMENT. 


63 


limb  are  readily  made  to  coincide  when,  in  adjusting  the  limb 
to  the  level  of  the  telescope,  the  arc  is  clamped  to  the  axis. 

The  usual  tangent  movement  to  the  telescope  axis 
serves  to  bring  the  vertical  limb  to  the  proper  elevation,  as 
hereafter  described.  A level  on  the  under  side  of  the  tele- 
scope, with  ground  vial  and  scale,  is  indispensable  in  the 
use  of  the  solar  attachment.  The  arcs,  verniers  and  hour- 
circle  are  all  graduated  on  silver.  Price  of  the  Solar  At- 
tachment, $60. 

Note. — See  pages  89-94  for  definitions  of  astronomical  terms. 

EXPLANATION  OF  THE  SOLAR  ATTACHMENT 

In  the  engraving  on  page  64  we  have  a graphic  illustra- 
tion of  the  solar  apparatus,  the  circles  shown  being  intended 
to  represent  those  supposed  to  be  drawn  upon  the  concave 
surface  of  the  heavens. 

When  the  telescope  is  set  horizontal  by  its  spirit-level, 
the  hour-circle  will  be  in  the  plane  of  the  horizon,  the  polar 
axis  will  point  to  the  zenith,  and  the  zeros  of  the  vertical 
arc  and  its  vernier  will  coincide.  Now,  if  we  incline  the 
telescope,  directed  north  as  shown  in  the  cut,  the  polar  axis 
will  descend  from  the  direction  of  the  zenith.  The  angle 
through  which  it  moves,  being  laid  off  on  the  vertical  arc, 
will  be  the  co-latitude  of  the  place  where  the  instrument  is 
supposed  to  be  used,  the  latitude  itself  being  found  by  sub- 
tracting this  number  from  ninety  degrees. 

When  the  sun  passes  above  or  below  the  equator,  its 
declination,  or  angular  distance  from  it,  as  given  in  the 
Ephemeris,  can  be  set  off  upon  the  declination  arc,  and  its 
image  brought  into  position  as  before. 

In  order  to  do  this,  however,  it  is  necessary  not  only 
that  the  latitude  and  declination  be  correctly  set  off  upon 


64 


SOLAR  ATTACHMENT \ 


GRAPHIC  ILLUSTRATION  OF  THE  SOLAR  APPARATUS 


SOLAR  ATTACHMENT. 


65 


their  respective  arcs,  but  also  that  the  instrument  be  moved 
in  azimuth  until  the  polar  axis  points  to  the  pole  of  the 
heavens,  or,  in  other  words,  is  placed  in  the  plane  of  the 
meridian;  and  thus  the  position  of  the  sun’s  image  will  in- 
dicate not  only  the  latitude  of  the  place,  the  declination  of 
the  sun  for  the  given  hour  and  the  apparent  time,  but  it  will 
also  determine  the  meridian,  or  true  north  and  south  line 
passing  through  the  place  where  the  observation  is  made. 

The  interval  between  two  equatorial 
lines,  c c,  as  well  as  between  the  hour 
lines,  b b,  is  just  sufficient  to  include  the 
circular  image  of  the  sun,  as  formed  by 
the  solar  lens  on  the  opposite  end  of  the  revolving  arm. 

Allowance  for  Declination  : Let  us  now  suppose  the 

declination.  observation  made  when  the  sun  has 
passed  the  equinoctial  point,  and  when 
its  position  is  affected  by  declination. 

By  referring  to  the  Ephemeris,  and  setting  off  on  the 
arc  the  declination  for  the  given  day  and  hour,  we  are  still 
able  to  determine  its  position  with  the  same  certainty  as  if 
it  remained  on  the  equator. 


0 i 

> 

When  the  sun’s  declination  is  south,  that  is,  from  the 
22d  of  September  to  the  20th  of  March  in  each  year,  the 
arc  is  turned  downward,  or  toward  the  plates  of  the  Transit, 
while  during  the  remainder  of  the  year  the  arc  is  turned 
from  the  plates. 

When  the  Solar  Attachment  is  accurately  adjusted  and 
the  transit  plates  made  perfectly  horizontal,  the  latitude  of 
the  place  and  the  declination  of  the  sun  for  the  given  day 
and  hour  being  also  set  off  on  their  respective  arcs,  and  the 
instrument  set  approximately  north  by  the  magnetic  needle, 
the  image  of  the  sun  cannot  be  brought  between  the  equatorial 
lines  until  the  polar  axis  is  placed  in  the  plane  of  the  meridian 


66 


SOLAR  ATTACHMENT. 


of  the  place , or  in  a position  parallel  with  the  axis  of  the 
earth . The  slightest  deviation  from  this  position  will  cause 
the  image  to  pass  above  or  below  the  lines,  and  thus  dis- 
cover the  error. 

From  the  position  of  the  sun  in  the  solar  system  we  thus 
obtain  a direction  absolutely  unchangeable,  from  which  to 
run  lines  and  measure  horizontal  angles. 

This  simple  principle  is  not  only  the  basis  of  the  con- 
struction of  solar  instruments,  but  it  is  the  only  cause  of 
their  superiority  over  instruments  having  the  ordinary  mag- 
netic needle.  For  in  an  instrument  having  a magnetic 
needle,  the  accuracy  of  the  horizontal  angles  indicated,  and 
therefore  of  all  the  observations  made,  depends  upon  the 
delicacy  of  the  needle  and  the  constancy  with  which  it 
assumes  a certain  direction,  called  the  magnetic  meridian. 

The  principal  causes  of  error  in  the  needle,  briefly  stated, 
are  the  dulling  of  the  pivot  and  the  resulting  injury  to  the 
error  jeweled-center,  the  loss  of  polarity  in  the 
in  needle,  needle,  the  influence  of  local  attraction, 
and  the  effect  of  the  sun’s  rays  producing  the  diurnal  varia- 
tion. From  all  these  imperfections  the  solar  instrument 
is  free. 

The  latitude  of  the  place  and  the  declination  of  the  sun 
being  set  off  upon  the  respective  arcs,  we  are  able  not  only 
to  run  the  true  meridian,  or  a due  east  and  west  course,  but 
also  to  set  off  horizontal  angles  with  minuteness  and  accu- 
racy from  a direction  which  never  changes  and  which  is 
unaffected  by  attraction  of  any  kind. 

ADVANTAGES  OF  THE  SOLAR  ATTACHMENT. 

From  what  has  been  already  said,  the  intelligent  sur^ 
veyor  will  readily  understand  that  the  more  perfect  horizon 
obtained  by  the  use  of  the  telescope  level,  and  the  use  of  a 


SOLAR  ATTACHMENT. 


67 


telescope  in  place  of  sights,  render  the  attachment  more 
accurate  than  the  ordinary  Solar  Compass. 

The  attachment  can  be  added  to  the  telescope  of  any 
good  Transit  at  a comparatively  small  cost,  thus  enabling 
the  surveyor  to  establish  the  true  meridian,  to  determine 
the  correct  latitude,  and  to  obtain  true  time  very  nearly. 

Its  adaptation  to  the  purposes  of  illustration  and 
instruction  in  practical  astronomy  in  colleges  and 
schools  will  occur  to  every  teacher ; and  it  furnishes 
for  the  Government  Surveyor  a long-sought  and  much- 
needed  instrument,  superior  to  the  Solar  Compass  form- 
erly used. 

In  experiments  made  by  us,  an  error  of  one-quarter  of 
a minute  in  the  direction  of  the  true  meridian,  or  in  lati- 
tude, could  be  easily  detected  by  observing  the  sun’s  image 
by  a magnifier  ; and  we  feel  confident  that  any  one  who 
uses  the  Solar  Attachment  will  be  surprised  and  delighted 
with  its  work.  When  not  in  use  it  should  be  removed  from 
the  telescope  and  packed  in  the  instrument  case,  and  the 
thin  sheath  put  on  the  polar  axis  and  kept  in  its  place  by 
the  screw  and  washer  of  the  socket. 

The  weight  of  the  Solar  Attachment  is  but  little  more 
than  ten  ounces,  and  is  so  distributed  as  not  to  disturb  the 
counterpoise  of  the  instrument,  thus  obviating  the  objec- 
tion which  has  hitherto  prevented  the  successful  use  of  the 
telescope  with  the  solar  apparatus. 

It  is  evident  that  all  Transits  to  which  the  Solar  Attach- 
ment is  to  be  applied  should  have  a horizontal  limb  and 
verniers,  and  should  be  furnished  with  a level  on  telescope, 
clamp  and  tangent  to  telescope  axis,  and  vertical  arc  and 
vernier.  They  should  also  have  a movable  compass-circle 
to  set  off  the  variation  of  the  needle,  and  be  leveled  by 
leveling-screws. 


68 


SOLAR  ATTACHMENT. 


It  will  be  understood  that  Transits  of  any  kind  which 
are  to  be  fitted  with  the  Solar  Attachment  must  be  in 
perfect  order,  especially  in  respect  to  the  sockets,  before 
correct  work  can  be  done. 

TO  RUN  LINES  WITH  THE  SOLAR  ATTACHMENT . 

Having  set  off  the  latitude  of  the  place  on  the  vertical 
arc,  and  the  declination,  corrected  for  refraction,  for  the 
given  day  and  hour  as  computed  from  the  tables  in  the 
Solar  Ephemeris,  the  instrument  being  also  carefully  leveled 
by  the  telescope  bubble,  set  the  horizontal  limb  at  zero  and 
clamp  the  plates,  loosen  the  lower  screw,  so  that  the  Transit 
moves  easily  upon  its  lower  socket,  set  the  instrument 
approximately  north  and  south,  with  the  object-glass  end  of 
the  telescope  towards  the  north,  turn  the  proper  solar  lens 
to  the  sun,  and,  with  one  hand  on  the  plates  and  the  other 
on  the  revolving  arm,  move  them  from  side  to  side  until 
the  sun’s  image  is  brought  between  the  equatorial  lines  on 
the  silver  plate. 

The  necessary  allowance  being  made  for  refraction,  the 
lower  clamp  of  the  instrument  should  now  be  fastened,  and 
any  further  lateral  movement  be  made  by  the  tangent  screw 
of  the  leveling-head.  The  telescope  will  be  in  the  true 
meridian,  and  may  be  used  like  the  sights  of  the  ordinary 
Solar  Compass,  but  with  far  greater  accuracy  and  satisfac- 
tion in  establishing  meridian  lines.  When  the  upper  or 
vernier  plate  is  unclamped  from  the  limb,  an  angle  read  by 
the  verniers  is  an  angle  from  the  meridian  ; and  thus  par- 
allels of  latitude  or  any  other  angles  from  the  true  meridian 
may  be  established,  as  with  the  Solar  Compass. 

The  bearing  of  the  needle,  when  the  telescope  is  on  the 
meridian,  will  also  give  the  variation  of  the  needle  at  the 
point  of  observation. 


SOLAR  ATTACHMENT. 


69 


If  the  instrument,  as  in  our  Surveyors’  Transits,  has  a 
movable  compass-circle,  the  variation  of  the  needle  can  be 
set  off  to  single  minutes,  the  needle  kept  at  zero,  or  “ with 
the  sun,”  and  thus  lines  be  run  by  the  needle  alone  when 
the  sun  is  obscured. 

REFRACTION  IN  DECLINATION. 

The  Table  of  Refractions  on  pages  70-74  is  calculated 
for  latitudes  between  2%°  and  70°  at  intervals  of  2^4°,  that 
being  as  near  as  is  required. 

The  declination  ranges  from  0°  to  20°  both  north  and 
south,  the  + declinations  being  north  and  the  — south, 
and  is  given  for  every  5°,  that  being  sufficiently  near  for  all 
practical  purposes.  The  hour  angle  in  the  first  column  in- 
dicates the  distance  of  the  sun  from  the  meridian  in  hours, 
the  refraction  given  for  0 hours  being  that  which  affects 
the  observed  declination  of  the  sun  when  on  the  meridian, 
commonly  known  as  meridional  refraction  ; the  refraction 
for  the  hour  just  before  or  after  noon  is  so  nearly  that  of 
the  meridian  that  it  may  be  called  and  allowed  as  the  same. 

When  the  table  is  used,  it  must  be  borne  in  mind  that 
when  the  declination  is  north,  or  + in  the  table,  the  refrac- 
tion is  to  be  added  ; when  the  declination  is  south,  or  — , 
the  refraction  must  be  subtracted.  It  will  be  noticed  that 
the  refraction  in  south,  or  — , declination  increases  very 
rapidly  as  the  sun  nears  the  horizon,  showing  that  observa- 
tions should  not  be  taken  with  the  sun  when  it  is  south  of 
the  equator,  less  than  one  hour  from  the  horizon. 


70 


REFRACTIONS  IN  DECLINATION 


A TABLE  OF  MEAN  REFRACTIONS  IN 
DEC  LIN  A TION 

To  apply  on  the  declination  arc  of  Solar  Attachment  of 
either  Compasses  or  Transits. 


Computed  by  Edward  W.  Arms,  C.  E.,  for  W.  & L.  E.  Gurley,  Troy,  N.  Y. 


w 

o 

DECLINATIONS. 

< 

For  Latitude  2°  30'. 

Cg 

D 

o 

33 

+20° 

+15° 

+10° 

+5° 

0° 

i 

Or 

o 

— 10° 

-15° 

o 

O 

Cvi 

1 

0 h. 

-18" 

—12" 

-07" 

—02" 

+02" 

07" 

12" 

18" 

23" 

2 

—18 

—12 

-07 

—02 

+02 

07 

12 

18 

23 

3 

—17 

—11 

—06 

—01 

i-03 

08 

13 

19 

25 

4 

—15 

—10 

-05 

0 

-f  05 

10 

15 

21 

27 

5 

—10 

—05 

0 

+05 

10 

15 

20 

26 

32 

For  Latitude  5°. 

0 h. 

—15" 

—10" 

—05" 

0" 

+05" 

10" 

15" 

20" 

27" 

2 

—15 

—10 

— 05 

0 

+05 

10 

15 

20 

27 

3 

—13 

—08 

-03 

+02 

07 

12 

17 

23 

29 

4 

—10 

—05 

0 

+05 

10 

15 

20 

27 

32 

5 

—05 

0 

4 05 

10 

15 

20 

27 

32 

40 

For  Latitude  7°  30'. 

0 h. 

—13" 

—08" 

—02" 

+02" 

08" 

13" 

18" 

24" 

29" 

2 

—12 

—07 

-01 

+03 

09 

14 

19 

25 

31 

3 

—10 

—05 

0 

+05 

10 

15 

20 

26 

32 

4 

—05 

0 

+05 

10 

15 

20 

26 

32 

39 

5 

+07 

12 

17 

23 

29 

38 

43 

51 

l'Ol" 

For  Latitude  10°. 

0 h. 

—10" 

—05" 

0" 

4 05" 

10" 

15  " 

20" 

26" 

32" 

2 

—07 

—03 

+02 

07 

12 

17 

22 

28 

34 

3 

-05 

0 

+03 

08 

13 

19 

25 

31 

38 

4 

0 

05 

10 

15 

20 

26 

32 

39 

46 

5 

+15 

20 

23 

32 

39 

46 

55 

1'06" 

119" 

For  Latitude  12°  30'. 

0 h. 

—08" 

-02" 

4 02" 

8" 

13" 

18" 

24" 

30" 

36" 

2 

—06 

00 

+ 05 

10 

15 

20 

26 

32 

39 

3 

+02 

07 

12 

17 

23 

29 

36 

43 

51 

4 

04 

09 

14 

20 

25 

31 

40 

48 

55 

5 

21 

27 

33 

40 

48 

57 

1'08" 

1'23" 

1'41" 

REFRACTIONS  IN  DECLINATION. 


71 


W 

i-l 

CD 

DECLINATIONS. 

K 

For  Latitude  15°. 

P 

o 

n 

+20° 

+15° 

+10° 

+5° 

0° 

-5° 

—10° 

—15° 

I 

uo 

o 

o 

0 h. 

—05" 

0" 

+05" 

10" 

15" 

21" 

27" 

33" 

40" 

2 

-03 

+02 

07 

12 

18 

23 

29 

36 

43 

3 

+ 01 

05 

11 

16 

22 

28 

34 

41 

49 

4 

08 

12 

19 

24 

30 

37 

44 

53 

1'04 

5 

29 

34 

41 

49 

59 

l'lO 

1'24 

1'43 

2 08 

For  Latitude  17 

° 30'. 

0 li. 

-02" 

+02" 

08" 

13" 

IS" 

24" 

30" 

36" 

44" 

2 

0 

05 

10 

15 

21 

27 

33 

40 

48 

3 

+02 

10 

15 

21 

27 

33 

40 

48 

57 

4 

13 

18 

23 

29 

35 

43 

51 

l'Ol 

1'13 

5 

34 

41 

49 

58 

l'lO 

1'23 

1'41 

2 06 

2 42 

For  Latitude  20°. 

0 h. 

0" 

05" 

10" 

15" 

21" 

27" 

33" 

40" 

48" 

2 

03 

07 

13 

18 

24 

30 

36 

44 

52 

3 

06 

13 

18 

24 

30 

36 

44 

52 

1'02 

4 

17 

22 

28 

35 

42 

50 

l'OO 

I'll 

126 

5 

39 

47 

57 

1'07 

1'20 

1'37 

2 00 

2 32 

325 

For  Latitude  22°  30'. 

0 h. 

02" 

08" 

13" 

18" 

24" 

30" 

36" 

44" 

52" 

2 

06 

11 

15 

21 

27 

33 

40 

48 

57 

3 

11 

15 

21 

27 

33 

40 

48 

57 

1'08 

4 

20 

26 

32 

39 

46 

56 

1'07 

1'19 

1 37 

5 

45 

53 

1'03 

1'16 

1'31 

1'52 

2 21 

3 07 

4 28 

For  Latitude  25°. 

0 h. 

05" 

10" 

15" 

21" 

27" 

33" 

40" 

48" 

57" 

2 

08 

14 

19 

25 

31 

38 

46 

54 

1'05 

3 

12 

18 

24 

30 

37 

44 

53 

1'04 

1 18 

4 

23 

29 

35 

45 

53 

1'03 

1'16 

1 31 

1 52 

5 

49 

59 

l'lO 

1'24 

1'52 

2 07 

2 44 

3 46 

5 43 

For  Latitude  27°  30'. 

Oh. 

08" 

13" 

18" 

24" 

30" 

36" 

44" 

52" 

1'02" 

2 

U 

16 

22 

28 

34 

41 

49 

l'OO 

1 10 

3 

17 

22 

28 

35 

42 

50 

l'OO 

1 11 

126 

4 

28 

35 

42 

50 

l'OO 

I'll 

1 26 

143 

2 09 

5 

54 

1'05 

1'18 

1'34 

154 

224 

311 

4 38 

8 15 

For  Latitude  30°. 

Oh. 

10" 

15" 

21" 

27" 

33" 

40" 

48" 

57" 

1'08" 

2 

14 

19 

25 

31 

38 

46 

54 

1'05 

1 18 

3 

20 

26 

32 

39 

47 

55 

1'06 

1 19 

1 36 

4 

32 

39 

46 

52 

1'06 

1'19 

1 35 

1 57 

2 29 

5 

1'00 

l'lO 

1'24 

1'52 

2 07 

244 

3 46 

5 43 

13  06 

72 


REFRACTIONS  IN  DECLINATION. 


M 

_> 

C5 

DECLINATIONS. 

< 

« 

p 

For  Latitude  32°  30'. 

O 

n 

+20° 

+15° 

+io° 

+5° 

0° 

-5° 

—10° 

-15° 

o 

§ 

1 

Oli. 

13" 

18" 

24" 

30" 

36" 

44" 

52" 

1'02" 

1'14" 

2 

17 

22 

28 

35 

42 

50 

l'OO 

1 11 

126 

3 

23 

29 

35 

43 

51 

l'Ol 

1 13 

128 

1 47 

4 

35 

43 

51 

l'Ol 

1'13 

127 

146 

213 

254 

5 

1'03 

1'15 

1'31 

1 53 

220 

3 05 

425 

7 36 

For  Latitude  35°. 

Oh. 

15" 

21" 

27" 

33" 

49" 

48" 

57" 

1'08" 

1'21" 

2 

20 

25 

32 

38 

46 

55 

1'05 

1 18 

1 35 

3 

26 

33 

39 

47 

56 

1'07 

121 

1 38 

200 

4 

39 

47 

56 

1'07 

1'20 

1 36 

1 59 

2 32 

3 25 

5 

1'07 

1'20 

1'38 

200 

234 

3 29 

5 14 

10  16 

For  Latitude  37°  30'. 

Oh. 

18" 

24" 

30" 

36" 

44" 

52" 

1'02" 

1'14" 

1'29" 

2 

22 

28 

35 

42 

50 

l'OO 

1 12 

1 26 

1 45 

3 

29 

36 

43 

52 

1'02 

114 

129 

149 

2 16 

4 

43 

51 

l'Ol 

1'13 

127 

1 49 

2 14 

2 54 

4 05 

5 

I'll 

1'26 

154 

210 

2 49 

3 55 

6 15 

14  58 

For  Latitude  40°. 

Oh. 

21" 

27" 

33" 

40" 

48" 

57" 

1'08" 

1'21" 

1'39'; 

2 

25 

32 

39 

46 

52 

1'06 

1 19 

135 

157 

3 

33 

40 

48 

57 

1'08 

121 

138 

2 02 

2 36 

4 

47 

55 

1'06 

1'19 

136 

158 

2 30 

3 21 

459 

5 

1'15 

1'31 

151 

2 20 

3 05 

4 25 

734 

2518 

For  Latitude  42°  30'. 

Oh. 

24" 

30" 

36" 

44" 

52" 

1'02" 

1'14" 

1'29" 

1'49" 

2 

28 

85 

39 

50 

l'OO 

112 

126 

145 

2 11 

3 

36 

43 

52 

1'02 

1 13 

1 29 

149 

2 17 

2 59 

4 

50 

1'00 

I'll 

126 

1 44 

2 10 

2 49 

355 

6 16 

5 

1'19 

1 36 

1 58 

2 30 

3 22 

500 

924 

For  Latitude  45°. 

Oh. 

27" 

33" 

40" 

48" 

57" 

1'08" 

1'21" 

1'39" 

2'02" 

2 

32 

39 

46 

52 

1'06 

1 19 

135 

157 

2 29 

3 

40 

47 

56 

107 

121 

138 

200 

234 

3 29 

4 

54 

1'04 

1'16 

1 33 

1 54 

2 24 

311 

438 

815 

5 

1'23 

141 

2 05 

2 41 

340 

540 

12  02 

For  Latitude  47‘ 

> 30'. 

Oh. 

30" 

36" 

44" 

52" 

1'02" 

1'14" 

1'29" 

1'49" 

2'18" 

2 

35 

42 

50 

1'00 

1 12 

126 

1 45 

2 01 

2 51 

3 

43 

51 

l'Ol 

1 13 

1 28 

147 

2 15 

256 

408 

4 

56 

1'09 

123 

140 

2 05 

240 

3 39 

5 37 

11  18 

5 

1'27 

1 48 

2 12 

2 52 

4 01 

630 

16  19 

REFRACTIONS  IN  DECLINATION. 


73 


w 

i-4 

O 

DECLINATIONS. 

« 

p 

For  Latitude  50°. 

o 

M 

+20° 

+ 15° 

+10° 

+5° 

0° 

-5° 

-10° 

-15° 

-20° 

Ob. 

33" 

40" 

48" 

57" 

ro8" 

1'21" 

1'39" 

2'02" 

2' 36" 

2 

38 

46 

55 

too 

1 18 

1 35 

157 

2 28 

319 

3 

47 

56 

1'06 

1 19 

1 36 

2 29 

2 31 

3 23 

5 02 

4 

1'02 

1'14 

129 

148 

2 16 

2 58 

418 

6 59 

19  47 

5 

130 

1 51 

2 19 

304 

4 22 

7 28 

2410 

For  Latitude  52°  30'. 

Ob. 

36" 

44" 

52" 

ro2" 

1/14" 

1'29" 

1'49" 

2'18" 

3'05" 

2 

43 

50 

59 

111 

126 

142 

223 

2 49 

3 55 

3 

50 

1'00 

I'll 

126 

145 

211 

2 51 

2 58 

622 

4 

1'05 

1 18 

135 

2 10 

228 

3 19 

4 53 

842 

5 

134 

156 

2 27 

316 

4 47 

8 52 

For  Latitude  55°. 

Oh. 

40" 

48" 

57" 

1'08" 

1'21" 

1'39" 

2'02" 

2'36" 

3'33" 

2 

46 

55 

1'05 

118 

134 

156 

2 30 

315 

4 47 

3 

55 

1'06 

1 19 

135 

158 

2 30 

3 21 

4 58 

9 19 

4 

l'lO 

1 23 

142 

2 06 

2 43 

3 44 

5 49 

12  41 

5 

137 

2 01 

2 34 

3 28 

515 

10  18 

For  Latitude  57 c 

’ 30'. 

Oh. 

44" 

52" 

l/02" 

ia4" 

1'29" 

1'49" 

2' 18" 

3'05" 

4/37" 

2 

50 

59 

111 

125 

143 

2 09 

2 47 

3 51 

6 04 

3 

58 

1'10 

124 

142 

2 07 

2 43 

3 45 

550 

12  47 

4 

I'll 

125 

143 

210 

2 50 

3 55 

6 14 

14  49 

5 

141 

2 06 

2 42 

342 

5 46 

12  26 

For  Latitude  60°. 

Oh. 

48" 

57" 

1'08" 

1'21" 

1'39" 

2'02" 

2'36" 

3'33" 

5'23" 

2 

54 

l/04 

1 17 

133 

154 

224 

3 12 

4 38 

8 15 

3 

1'03 

1 15 

1 30 

151 

220 

3 04 

424 

7 31 

24  44 

4 

1 18 

134 

156 

2 28 

3 18 

4 50 

853 

5 

145 

211 

2 50 

3 57 

6 21 

15  32 

For  Latitude  62°  30'. 

0 h. 

52" 

1'02" 

1'14" 

1'29" 

1'50" 

2'18" 

3'00'' 

4'17" 

7'13" 

2 

58 

109 

123 

141 

2 06 

2 43 

3 44 

5 50 

12  44 

3 

1'07" 

123 

138 

2 01 

2 35 

3 30 

516 

10  24 

4 

123 

140 

205 

240 

3 40 

5 37 

1150 

5 

148 

217 

2 59 

414 

7 03 

For  Latitude  65°. 

0 h. 

57" 

1'08" 

1'21" 

1'39" 

2'02" 

2'36" 

3'33" 

5'23" 

10'51" 

2 

1'03" 

116 

131 

152 

2 21 

3 07 

4 28 

7 44 

3 

112 

127 

146 

212 

252 

4 02 

6 33 

4 

127 

147 

213 

2 54 

4 05 

6 40 

5 

152 

2 22 

3 08 

4 30 

7'52 

HOUR  ANGLE. 


74 


REFRACTIONS  IN  DECLINATION. 


DECLINATIONS. 


For  Latitude  67°  30'. 


f20° 

+ 15°  | 

+10° 

+5° 

0° 

-5°  I 

i 

t-1 

o 

o 

-15° 

-20° 

1'02" 

114" 

1'29" 

1'50" 

218" 

3'00" 

417" 

713" 

108 

122 

140 

2 03 

2 39 

3 37 

5 32 

1128 

117 

1 34 

155 

226 

314 

444 

834 

132 

153 

223 

314 

4 35 

8 05 

156 

228 

317 

440 

8 51 

For  Latitude  70°. 


0 h. 

ro8" 

1'21" 

1'39" 

2'02" 

2'36" 

3'33" 

5'23" 

10'51" 

2 

114 

129 

150 

218 

300 

417 

713 

3 

123 

143 

2 05 

241 

341 

5 59 

12 15 

4 

137 

209 

234 

3 23 

5 20 

10 12 

5 

2 02 

2 33 

327 

511 

10  05 

COMPUTING  DECLINATIONS. 


75 


TO  COMPUTE  THE  DECLINATION , 


Suppose  the  corrected  declination  is  desired  for  the  dif- 
ferent hours  of  April  16,  1902,  at  Troy,  N.  Y. 

The  latitude  is  42^  44'. 

The  longitude  is  four  hours,  fifty-four  minutes,  and 
forty  seconds,  or  practically  five  hours  ; so  that  the  declina- 
tion given  in  the  Ephemeris  for  apparent  noon  of  that  day 
at  Greenwich  would  be  that  of  7 A.  M.  at  T roy.  Declination 
at  Greenwich  at  noon  of  April  16,  1902,  N.  9°  53'  14". 4. 


N.  9°53'14".4  + ref.  5 hrs.  1'58"  = 9°55'12"  = dec.  for  7 A.  M. 
add  hr.  dif.  53". 44 


9°54'07".84  + “ 4 


“ I'll"  = 


9°55'19"  = “ “ 8 “ 


53".  44 

9°55'01".28  + “ 3 “ 
53". 44 

9°55'54".72  + “ 2 “ 
53". 44 

9°56'48".16  + “ 1 “ 
53". 44 

9°57'41".60  + “ 0 “ 
53".  44 

9°58'35".04  + “ 1 “ 
53". 44 

9°59'28".48  + “ 2 “ 
53". 44 

10°00'21".92  + “ 3 “ 


II 

csi 

lO 

9°55'53"  = 

a 

t ( 

9 “ 

39"  = 

9°56'34"  — 

a 

a 

10  “ 

CO 

Cfc 

II 

9°57'24"  = 

< ( 

( < 

11  “ 

36"  = 

9°58'18"  = 

a 

< ( 

12  M. 

II 

■ cb 

CO 

9°59'11"  = 

t( 

(( 

1 P.  M 

CO 

ZD 

II 

10°00'07"  = 

a 

a 

2 “ 

52"  = 

10°01'14"  = 

t( 

it 

3 “ 

53".  44 

10°01'15".36  + “ 4 “ I'll"  = 10°02'26"  = “ “ 4 “ 

53". 44 

10°02'08".80  -h  “ 5 “ 1'58"  = 10°03'07"  = “ “ 5 “ 


76 


COMPUTING  DECLINA  TIONS. 


Again,  suppose  the  corrected  declination  is  desired  for 
the  different  hours  of  October  16,  1902,  at  Troy,  N.  Y. 

The  declination  at  Greenwich,  noon,  or  Troy  7 A.  M., 
being  now  South  or  minus  and  the  hourly  difference  also 
minus,  they  must  be  added,  while  the  refraction  being  plus 
must  be  subtracted  ; thus  : 


S.  8°38'21"9  - ref.  5 hrs.  9'24"  = 8°28'58"  = dec.  for  7 A.  M. 
55".  44 


8°39'17".34  - “ 4 
55".  44 

8°40'12"  78  - “ 3 
55". 44 

8°41'08".22  — “ 2 
55". 44 

8°42'03"66  - “ 1 
55". 44 

8°42'59".10  — “ 0 
55". 44 

8°43'54"  54  - “ 1 
55". 44 

8°44r49"  98  — “ 2 
55". 44 

8°45'45".42  — “ 3 
55". 44 

8°46'40".86  — “ 4 
55". 44 

8°47'36".30  — “ 5 


“ 2'49" 

“ 1'49" 

“ 1'26" 

“ 1'14"  = 8°40'40" 
“ 1'14"  = 8°41'45" 
“ 1'14"  = 8°42'31" 
“ 1'26"  = 8°43'24" 
“ 1'49"  = 8°43'56" 
“ 2'49"  = 8°43'52" 
“ 9'24"  = 8°38'12" 


_ <<  a 9 << 

_ 10  “ 

— n ((  a 

= “ “ 12  M. 

= “ “ 1 P.  M 

_ <<  2 te 

— t(  6<  g a 

— ((  a ^ “ 

a it  & (t 


= 8°36'28r/  =z  « « 8 «' 

= 8°38'23" 

= 8°39'42" 


We  believe  it  will  be  found  that  the  use  of  the  table  as 
illustrated  above  will  not  only  relieve  the  surveyor  of  the 
perplexity  hitherto  attending  the  subject  of  refractions,  but 
will  also  enable  him  to  secure  more  accurate  results  than 
were  possible  by  the  methods  usually  given. 


LA  TITUDE. 


77 


The  calculation  of  the  declination  for  the  different 
hours  of  the  day  should,  of  course,  be  made  and  noted 
before  the  surveyor  begins  his  work,  that  he  may  lay  off 
the  change  from  hour  to  hour,  from  a table  prepared  as 
before  described. 

TO  FIND  THE  LA  TITUDE. 

First,  level  the  instrument  very  carefully,  using,  as 
before,  the  level  of  the  telescope  until  the  bubble  will 
remain  in  the  middle  during  a complete  revolution  of  the 
instrument,  the  tangent  movement  of  the  telescope  being 
used  in  connection  with  the  leveling  screws,  and  the  axis 
of  the  telescope  being  firmly  clamped. 

Next,  clamp  the  vertical  arc,  so  that  its  zero  and  the  zero 
of  its  vernier  coincide  as  near  as  may  be,  and  then  bring 
them  into  exact  line  by  the  tangent  screw  of  the  vernier. 

Then,  having  the  declination  of  the  sun  for  12  o’clock  of 
the  given  day  as  affected  by  the  meridional  refraction  care- 
fully set  off  upon  the  declination  arc,  note  also  the  equa- 
tion of  time  ; and  fifteen  or  twenty  minutes  before  noon, 
the  telescope  being  directed  to  the  north  and  the  object- 
glass  end  lowered  until,  by  moving  the  instrument  upon  its 
spindle  and  the  declination  arc  from  side  to  side,  the  sun’s 
image  is  brought  nearly  into  position  between  the  equatorial 
lines.  Now  bring  the  declination  arc  directly  in  line  with 
the  telescope,  clamp  the  axis,  and  with  the  tangent  screw  of 
the  telescope  axis  bring  the  image  precisely  between  the 
lines,  following  the  sun’s  motion  as  the  image  runs  below 
the  lower  equatorial  line,  or,  in  other  words,  as  long  as  the 
sun  continues  to  rise  in  the  heavens. 

When  the  sun  reaches  the  meridian  the  image  will 
remain  stationary  in  altitude  for  an  instant,  and  will  then 
begin  to  rise  on  the  plate. 


78 


LA  TITUDE. 


The  moment  the  image  ceases  to  run  below  is,  of  course, 
apparent  noon,  when  the  index  of  the  hour  arc  should  indi- 
cate XII.,  and  the  latitude  be  determined  by  the  reading  of 
the  vertical  arc. 

The  angle  through  which  the  polar  axis  has  moved  in 
the  operation  just  described  is  measured  from  the  zenith 
instead  of  the  horizon,  as  in  the  Solar  Compass,  so  that 
the  angle  read  on  the  vertical  limb  is  the  complement  of 
the  latitude. 

The  latitude  itself  is  readily  found  by  subtracting  this 
angle  from  90Q;  thus  at  Troy  the  reading  of  the  limb  being 
found  as  above  directed  to  be  47°  16',  the  latitude  will  be 
90°  — 47°  16'  = 42°  44'.  The  latitude  may  also  be  read 
direct  by  referring  to  the  inner  row  of  figures  on  the  arc, 
beginning  with  90  in  the  middle  and  reading  to  10  on  either 
side. 

With  a transit  having  both  vertical  and  horizontal  limbs, 
direct  observations  may  be  taken  on  the  sun  to  find  the 
direct  meridian.  The  best  time  of  day  is  about 
observation,  three  hours  before  or  after  noon.  A col- 
ored or  smoked  glass  darkener  will  be  necessary  over  the 
eyepiece  to  protect  the  eye.  The  observations  to  be  taken 
are  those  of  the  altitude  of  the  sun  and  its  horizontal  angle 
from  a fixed  point,  at  the  same  instant.  It  is  best  to  take  a 
number  of  these,  say,  three  or  five,  so  as  to  check  ; and  if 
the  telescope  is  reversed  and  another  set  taken,  the  mean 
of  the  two  sets  will  eliminate  many  inaccuracies.  It  is  also 
an  advantage  to  use  the  lower  limb  of  the  sun  in  the  morn- 
ing and  the  upper  limb  in  the  afternoon  — it  being  easier  to 
judge  the  tangency  of  image  and  cross-wires.  Allowance 
is  then  made  for  the  semi-diameter  of  the  sun,  which  varies 
from  15f  to  16^  minutes.  It  will  be  sufficiently  close  to 
have  the  vertical  wire  bisect  the  sun,  but  the  altitude  must 


DIRECT  OBSERVATION. 


79 


be  taken  with  care.  It  will  be  understood  that  the  transit 
must  be  accurately  leveled  and  adjusted. 

To  reduce  the  observations  there  are  many  forms,  all 
deduced  from  the  same  formula.  The  form  much  favored 

is  tan2  1A  = Sin  [S— (90°— alt.)] . sin  [S— (90°— lat.)] 

2 sin  S.  sin  [S — (90° — dec.)] 

reduction-  which  “A”  is  the  azimuth  of  the  sun  or 
formula.  horizontal  distance  from  the  meridian,  and 
“ S ” is  one-half  the  sum  of  (90Q — alt.  corrected  for  refrac- 
tion)-f  (90° — lat.) + (90° — dec.)  Note  the  sign  of  the  decli- 
nation. When  South  would  be  (90° — ( — dec.)  = 90°  + dec. 

Example:  Place,  Troy,  N.  Y.  Time  3h.  30m.  P.  M., 

March  31,  1902. 


The  horizontal  angle  from  a fixed  point  to  sun’s  center,  . 241°  46' 

Observed  altitude  of  upper  limb  of  sun, 30°  31/  10" 

Obs.  alt.  — refraction  1°  40' — semi  diameter  16':=  alt.  of 

sun’s  center, 30°  13'  30" 

Declination  for  day  and  hour, 4°  30'  30" 

Latitude, • 42°  44' 

90° — alt.  = 59°46'30",  90°  — dec.  = 85°29'30", 

90° — lat.=  47°  16',  2 S = 192°  31',  S = . . . . 96°  16' 


log.  sin  [S—  (90°— alt.)]  = 9.77430 
log.  sin  [S— (90°— lat.)]  = 9.87778 

9.65208 

log.  sin  S = 9.99740 

log.  sin  [S — (90° — dec.)]  = 9.27173 

9.26913 

log.  tan2  % A = 0.38295 
log.  tan  % A — 0.19148 

% A = 57°  14'  25"  and  A = 114°  28'  50"  West  of  North. 

If  in  the  morning  would  be  East  of  North. 

Apply  this  to  the  horizontal  angle  from  the  fixed  point 
to  the  sun  and  we  have  356°  14'  50",  which  is  the  reading 
of  the  horizontal  limb  when  the  telescope  is  pointed  North, 


80 


DIRECT  OBSERVATION. 


Set  this  reading  off  on  the  limb  and  the  telescope  will  be  in 
the  plane  of  the  meridian. 

A table  of  Mean  Refractions  due  to  altitude. 

Bar.  30  ins.,  Ther.  50°  F.,  always  minus. 


App.  alt. 

Ref. 

App.  alt. 

Ref. 

App.  alt. 

Ref. 

App.  alt. 

Ref. 

5° 

5'  52// 

10° 

W 19" 

20° 

2'  39" 

50° 

O'  49" 

6° 

8'  28" 

12° 

4/  17 // 

25° 

2'  04" 

60° 

0'  34" 

7° 

7'  24" 

14° 

3'  49" 

30° 

V 41" 

70° 

0'  21" 

8° 

6'  33" 

16° 

3'  20" 

35° 

1'  23" 

80° 

O'  10" 

9° 

5/  53" 

18° 

2'  57" 

40° 

1'  09" 

90° 

0'  0" 

A Table  of  Semi  Diameter  of  the  Sun: 


Jan.  1,  16'  17" 
Feb.  1,  16'  14" 
Mar.  1,  16'  09" 


April  1,  16'  01" 
May  1,  15'  53" 
June  1,  15'  47" 


July  1,  15'  45" 
Aug.  1,  15'  47" 
Sept.  1,  15'  42" 


Oct  1,  16'  00" 
Nov.  1,  16'  08" 
Dec.  1,  16'  14" 


If  desired,  we  will  furnish,  at  a cost  of  $5.00,  a simple 
solar  screen  arranged  to  clamp  to  the  eyepiece  end  of  the 
telescope,  and  detachable  at  will.  On 
solar  screen.  screen  the  image  of  the  sun  and 

cross-wires  can  readily  be  observed.  A greater  movement 
to  the  eyepiece  is  required,  however. 


ADVANTAGES  OF  THE  SOLAR, . 


81 


* 

TIME  FOR  USING  THE  SOLAR. 

The  Solar,  like  the  ordinary  instrument,  can  be  used  at 
all  seasons  of  the  year,  the  most  favorable  time  being,  of 
course,  in  the  summer,  when  the  declination  is  north  and 
the  days  are  long  and  more  generally  fair.  It  is  best  not 
to  take  the  sun  at  morning  and  evening  when  it  is  within 
half  an  hour  of  the  horizon,  nor  at  noon,  for  about  the 
same  interval  before  and  after  it  passes  the  meridian. 


ADVANTAGES  OF  THE  SOLAR  IN  SURVEYING. 

While  the  Solar  is  indispensable  in  the  surveys  of  public 
lands,  it  also  possesses  important  advantages  over  the  mag- 
netic needle  Compass  when  used  in  the  ordinary  surveys  of 
farms,  and  similar  work.  For  not  only  can  lines  be  run  and 
angles  be  measured  without  regard  to  the  diurnal  variation 
or  the  effect  of  local  attraction,  but  the  bearings  being 
taken  from  the  true  meridian  will  remain  unchanged  for  all 
time. 

In  favorable  weather  surveys  can  be  made  more  rapidly 
with  it  than  with  the  ordinary  needle-instrument  ; there 
being  no  time  consumed  in  waiting  for  the  needle  to  settle, 
or  in  avoiding  the  errors  of  local  attraction. 

When  the  sun  is  obscured  the  lines  may  be  run  by  the 
needle  alone,  it  being  always  kept  with  the  sun,  or  at  0 on 
its  arc,  thus  indicating  the  direction  of  the  true  meridian. 
The  sun,  however,  must  ever  be  regarded  as  the  most 
reliable  guide,  and  should,  if  possible,  be  taken  at  every 
staiion. 


82 


PATENT  LATITUDE-LEVEL, 


4 

PATENT  LATITUDE-LEVEL. 

% 

This  attachment,  shown  in  the  cut  on  page  31,  is  used 
for  recovering  the  latitude  on  a Solar  Transit  without 
referring  to  the  vertical  arc  ; and  generally  for  setting  the 
telescope  at  any  desired  angle  in  running  grades  and 
similar  work. 

It  consists  of  a level  connected  by  a short  conical 
socket  with  the  end  of  the  telescope  axis,  to  which  it  is 
clamped  by  a milled  head  screw,  and  made  adjustable  by  a 
tangent  screw  and  spring  on  the  enlarged  end  of  the  tube. 
When  the  clamp-screw  is  released  the  level  turns  vertically 
upon  the  axis,  and  can  thus  be  set  at  any  angle  with  the 
telescope,  the  final  adjustment  being  made  by  the  tangent 
screw. 

The  latitude  being  set  off  upon  the  vertical  arc  as 
usual,  the  level  is  clamped  and  brought  into  the  middle  as 
above  described. 

The  telescope  may  then  be  released  and  used  in  running 
lines,  until  it  is  desired  to  recover  the  latitude  again  ; this 
is  easily  and  accurately  done  by  the  level  alone  without 
referring  to  the  vertical  arc. 

Its  use  in  running  any  desired  grade  is  readily  under- 
stood. 

We  make  no  additional  charge  for  this  attachment  when 
furnished  with  a new  solar  instrument  ; when  added  to  our 
old  Solar  Transits  the  cost  will  be  $6.00. 


JONES'  LATITUDE  ARC . 


83 


R.  M.  JONES'  LATITUDE  ARC. 

In  this  attachment  the  usual  vertical  arc  is  omitted,  and 
replaced  by  a double  latitude  arc  attached  to  the  under 
side  of  the  telescope,  as  shown  above.  The  smaller  arc, 
having  its  center  directly  under  the  cross-bar  of  the 
telescope,  has  an  arm  with  vernier  reading  the  arc  to  single 
minutes,  and  carries  also  a level-tube  open  at  both  top  and 
bottom,  with  a scale  over  each  opening. 

In  obtaining  latitudes  with  this  attachment,  the  declina- 
tion being  set  off  as  usual,  the  level-bubble  should  be 
brought  into  the  middle  of  its  scale  when  the  sun  is  on  the 
meridian. 


84 


JONES'  LATITUDE  ARC. 


The  reading  of  the  smaller  arc  then  gives  the  latitude 
of  the  place,  and  in  all  further  observations  of  the  latitude 
reference  is  made  to  the  level  rather  than  to  the  divisions, 
the  level  being  easily  brought  into  the  middle  of  the  scale. 
This  enables  the  surveyor  to  recover  the  latitude  more 
rapidly  than  with  the  ordinary  vertical  arc. 

Minute  changes,  as  long  lines  are  run  either  north  or 
south,  may  be  computed  and  set  off  on  the  larger  arc, 
which  reads  by  its  vernier  to  ten  seconds  of  a degree. 

The  solar  apparatus  can  also  be  used  when  the  telescope 
is  revolved  and  the  apparatus  brought  below  it,  the  latitude 
being  now  ascertained  by  reference  to  the  other  side  of  the 
level  with  its  scale. 

But  one  test  of  the  adjustment  of  this  attachment  is 
required  : — that  both  arcs  should  read  zero  when  the 
telescope  is  made  horizontal  by  its  long  level,  and  the 
smaller  level  of  the  arc  below  is  also  brought  to  the  middle 
of  its  scale. 

If  not  correct,  they  may  be  adjusted  by  loosening  the 
screws  by  which  each  arc  is  confined,  and  moving  the  arcs 
until  the  zeros  of  both  are  in  coincidence  with  the  zeros  of 
their  verniers,  care  being  taken  to  set  the  screws  firmly 
again. 

PRICES. 


Jones’  Latitude  Arc,  with  reversible  level-bubble 173.00 

When  furnished  with  a new  Transit  of  our  make  in  place  of  the 
ordinary  vertical  arc,  the  Jones’  Latitude  Arc,  with  reversible 

level-bubble,  increases  the  cost  of  the  instrument 55.00 

Thus  : The  Light  Mountain  Transit,  with  Solar  Attachment  and 

Jones’  Latitude  Arc,  costs 300.00 


ADJUSTMENTS  OF  THE  SOLAR. 


85 


TO  ADJUST  THE  SOLAR  ATTACHMENT. 

The  declination  arm  is  first  detached  by  removing  the 
solar  lenses  c^amP  and  tangent  screws  and  the  center 
and  lines,  with  its  small  screws,  by  which  the  arm  is 
attached  to  the  arc. 

The  adjuster,  which  is  a short  bar  furnished  with  every 
instrument,  is  then  substituted  for  the  declination  arm,  the 
center  screwed  into  its  place  at  one  end,  and  the  clamp- 
screw  into  the  other,  being  inserted  through  the  hole  left  by 
the  removal  of  the  tangent  screw,  thus  securing  the  adjuster 
firmly  to  the  arc. 

The  declination  arm  is  then  placed  on  the  adjuster,  one 
end  is  turned  to  the  sun,  and  brought  into  such  a position 
that  the  image  of  the  sun  is  brought  precisely  between  the 
equatorial  lines  on  the  opposite  plate. 

Carefully  turn  the  arm  over,  until  it  rests  upon  the 
adjuster  by  the  opposite  faces  of  the  rectangular  blocks, 
and  again  observe  the  sun’s  image.  If  it  remains  between 
the  lines  as  before,  the  arm  is  in  adjustment.  If  not, 
loosen  the  three  small  screws  and  move  the  silver  plate 
under  their  heads  until  one-half  the  error  in  the  position  of 
the  sun’s  image  is  removed. 

Bring  the  image  again  between  the  lines,  and  repeat  the 
operation  as  above  on  both  ends  of  the  arm,  until  the  image 
will  remain  between  the  lines  of  the  plate  in  both  positions 
of  the  arm,  when  it  will  be  in  proper  adjustment,  and  the 
arm  may  be  replaced  in  its  former  position  on  the  attach- 
ment. This  adjustment  is  very  rarely  needed  in  our  instru- 
ments, the  lenses  being  cemented  in  their  cells  and  the 
plates  securely  fastened. 


86 


ADJUSTMENTS  OF  THE  SOLAR. 


To  adjust  the  Vernier  of  the  Declination  Arc  : Set 

declination  t^ie  vernier  at  zero,  and  then  raise  or 
arc.  lower  the  telescope  until  the  sun’s  image 

appears  exactly  between  the  equatorial  lines. 

Having  the  telescope  axis  clamped,  carefully  revolve 
the  arm  until  the  image  appears  on  the  other  plate.  If 
precisely  between  the  lines,  the  adjustment  is  complete  ; 
if  not,  move  the  declination  arm  by  its  tangent  screw  until 
the  image  will  come  precisely  between  the  lines  on  the 
two  opposite  plates  ; clamp  the  arm  and  remove  the  index 
error  by  loosening  two  screws  that  fasten  the  vernier;  place 
the  zeros  of  the  vernier  and  limb  in  exact  coincidence, 
tighten  the  screws,  and  the  adjustment  is  complete. 

To  adjust  the  Polar  Axis  : First,  level  the  instrument 

carefully  by  the  long  level  of  the  telescope,  using  in  the 

operation  the  tangent  movement  of  the 
POLAR  AX)S.  . . 11,1 

telescope  axis  in  connection  with  the  level- 
ing-screws, until  the  bubble  will  remain  in  the  middle  dur- 
ing a complete  revolution  of  the  instrument  upon  its  axis. 

Place  the  solar  apparatus  upon  the  axis  and  see  that  it 
moves  easily  around  it  ; bring  the  declination  arm  in  the 
same  vertical  plane  with  the  telescope,  place  the  Adjusting- 
Level,  No.  196  (see  below),  upon  the  top  of  the  rectangu- 
lar blocks,  and  bring  the  bubble  of  the  level  into  the  middle 
by  the  tangent  screw  of  the  declination  arc. 


NO.  196. 

STRIDING  OR  ADJUSTING-LEVEL. 


ADJUSTMENTS  OF  THE  SOLAR. 


87 


Then  turn  the  arc  half-way  around,  bringing  it  again 
parallel  with  the  telescope,  and  note  the  position  of  the 
level.  If  in  the  middle,  the  polar  axis  is  vertical  in  that 
direction  ; if  not  in  the  middle,  correct  one-half  of  the  error 
by  the  capstan-head  adjusting  screws  under  the  base  of  the 
polar  axis,  moving  each  screw  of  the  pair  the  same  amount, 
but  in  an  opposite  direction.  Bring  the  level  to  the  middle 
again  by  the  tangent  screw  of  the  declination  arc,  and 
repeat  the  operation  as  before,  until  the  bubble  will  remain 
in  the  middle  when  the  adjusting-level  is  reversed. 

Pursue  the  same  course  in  adjusting  the  arc  in  the  sec- 
ond position,  or  over  the  telescope  axis,  and  when  com- 
pleted the  level  will  remain  in  the  middle  during  an  entire 
revolution  of.  the  arc,  showing  that  the  polar  axis  is  at 
right  angles  with  the  level  under  the  telescope,  or  truly 
vertical. 

As  this  is  by  far  the  most  delicate  and  important 
adjustment  of  the  Solar  Attachment,  it  should  be  made 
with  the  greatest  care,  the  bubble  kept  perfectly  in  the 
middle  and  frequently  inspected  in  the  course  of  the  ad- 
justment. 

The  Adjusting-Level  in  the  operation  just  described  is 
supposed  to  be  itself  in  adjustment  ; but  if  not,  it  can  be 
easily  corrected  by  the  screw  shown  at  one  end,  when  re- 
versed upon  a plane  surface,  exactly  as  a mason’s  level  is 
adjusted. 

To  adjust  the  Hour-Arc  : Whenever  the  instrument  is 

set  in  the  meridian,  as  will  be  hereafter  described,  the  index 
of  the  hour-arc  should  read  apparent  time. 
If  not,  loosen  the  two  flat  head  screws  on  the 
top  of  the  hour-circle,  and  with  the  hand  turn  the  circle 
around  until  it  does,  fasten  the  screws  again,  and  the 
adjustment  will  be  complete. 


88 


ADJUSTMENTS  OF  THE  SOLAR. 


To  obtain  mean  time , the  correction  of  the  equation  for 
the  given  day,  as  found  in  the  Nautical  Almanac,  should 
always  be  applied. 

To  obtain  standard  time , apply  the  difference  in  longi- 
tude between  the  locality  and  the  nearest  standard  meridian 
to  the  mean  time. 


ASTRONOMICAL  TERMS. 


SUN. 


EARTH. 


A 1 TE  DEFINE,  in  the  few  pages  following,  the  terms 
1 ^ employed  in  the  use  and  adjustment  of  the  solar 
apparatus,  as  being  of  service  to  one  not  familiar  with 
solar  instruments. 

The  Sun  is  the  center  of  the  solar  system, 
remaining  constantly  fixed  in  its  position,  although, 
for  the  sake  of  convenience,  often  spoken  of  as  in  motion 
around  the  qarth. 

The  Earth  makes  a complete  revolution 
around  the  sun  in  three  hundred  and  sixty-five 
days,  five  hours,  forty-eight  minutes  and  forty-six  seconds. 

It  also  rotates  about  an  imaginary  line  passing  through 
its  center,  and  termed  its  axis,  once  in  twenty-three  hours, 
fifty-six  minutes  and  four  seconds,  mean  time,  turning  from 
west  to  east. 

The  Poles  are  the  extremities  of  the  axis  ; that  in  our 
own  hemisphere,  known  as  the  north  pole,  if 
produced  indefinitely  toward  the  concave  sur- 
face of  the  heavens,  would  reach  a point  situated  near  the 
polar  star,  and  called  the  north  pole  of  the  heavens. 

The  Equator  is  an  imaginary  line  passing 
around  the  earth,  equi-distant  from  the  poles, 
and  in  a plane  at  right  angles  with  the  axis. 

If  the  plane  of  the  celestial  equator  be  produced  to  the 
heavens,  it  forms  what  is  termed  the  equator. 

The  Orbit  of  the  earth  is  the  path  in  which  it  moves  in 
making  its  yearly  revolution.  If  the  plane  of 
this  orbit  were  produced  to  the  heavens,  it  would 
form  the  ecliptic,  or  the  sun’s  apparent  path  in  the  heavens. 

89 


POLES. 


EQUATOR. 


ORBIT. 


90 


ASTRONOMICAL  TERMS. 


The  earth’s  axis  is  inclined  to  its  orbit  at  an  angle  of 
about  23°  27',  making  an  angle  between  the  earth’s  orbit 
and  its  equator,  or  between  the  celestial  equator  and  the 
ecliptic,  of  the  same  amount. 

The  Equinoxes  are  the  two  points  in 

EQUINOXES.  M V 

which  the  ecliptic  and  the  celestial 

equator  intersect  one  another. 

The  Declination  of  the  Sun  is  its  angular  distance  north 
or  south  of  the  celestial  equator ; when  the  sun  is  at 
declination  ^ie  equinoxes,  that  is,  about  the  21st  of 
March  and  the  21st  of  September  of  each 


OF  SUN. 


year,  its  declination  is  0,  or 


it  is  said  to  be  on  the 
declination  increases  from 
hour,  until  on  the  21st  of 
it  is  23°  27'  distant  from 


equator  ; from  these  points  its 
day  to  day,  and  from  hour  to 
June  and  the  21st  of  December 
the  equator. 

It  is  the  declination  which  causes  the  sun  to  appear  so 
much  higher  in  summer  than  in  winter,  its  altitude  in  the 
heavens  being  about  46°  54'  more  on  the  21st  of  June 
than  it  is  on  the  21st  of  December. 

The  Horizon  of  a place  is  the  surface  which  is  defined 
by  a plane  supposed  to  pass  through  the  place  at  right 
angles  with  a vertical  line,  and  to  bound  our 
vision  at  the  surface  of  the  earth.  The  hori- 
zon, or  a horizontal  surface,  is  determined  by  the  surface 
of  any  liquid  when  at  rest,  or  by  the  spirit-levels  of  an 
instrument. 

The  Zenith  of  any  place  is  the  point 
ZENITH.  J . 

directly  overhead,  in  a line  at  right  angles 

with  the  horizon. 

The  Meridian  Circle  of  any  place  is  a 
meridia  . great  circie  passing  through  the  zenith  of  a 

place  and  the  poles  of  the  earth. 


ASTRONOMICAL  TERMS. 


91 


The  meridian,  or  true  north  and  south  line  of  any  place, 
is  the  line  determined  by  the  intersection  of  the  plane  of 
the  meridian  circle  with  the  plane  of  the  horizon. 
meridian  The  Meridian  Altitude  of  the  sun  is  its 

altitude.  angular  elevation  above  the  horizon,  when 
passing  the  meridian  of  the  place. 

LATITUDE  The  Lat^tu<^e  a Place  is  its  distance 

north  or  south  of  the  equator,  measured  on  the 
meridian.  At  the  equator  the  latitude  is  0°,  at  the  poles  90°. 

The  Longitude  of  a place  is  its  angular  distance  east  or 
west  of  a given  place  taken  as  the  starting- 
point  or  first  meridian  ; it  is  measured  on  the 
equator  or  on  any  parallel  of  latitude. 

In  the  Nautical  Almanac,  which  is  commonly  used  with 
a solar  instrument,  the  longitude  of  the  principal  places  in 
the  United  States  is  reckoned  from  Greenwich,  England, 
and  expressed  both  in  degrees  and  hours. 

The  Zenith  Distance  of  any  heavenly  body  is  its' 
ZENITH  angular  distance  north  or  south  of  the  zenith 
distance,  of  a place,  measured  when  the  body  is  on 


LONGITUDE, 


the  meridian. 

Suppose  a person  to  be  on  the  equator  at  the  time  of  an 
equinox  ; the  sun,  when  on  the  ^meridian,  would  be  in  the 
zenith  of  the  place,  and  the  poles  of  the  earth  would  lie  in 
the  plane  of  its  horizon. 

Disregarding,  for  the  present,  the  declination  of  the 
sun,  let  us  suppose  that  the  person  travels  toward  the  north 
pole.  As  he  passes  to  the  north,,  the  sun  will  descend  from 
the  zenith,  and  the  pole  will  rise  from  the  horizon  in  the 
same  proportion,  until  when  he  arrives  at  the  north 
pole  of  the  earth  the  sun  will  have  declined  to  the 
horizon,  and  the  pole  of  the  heavens  will  have  reached  the 
zenith. 


92 


ASTRONOMICAL  TERMS . 


The  altitude  of  the  pole  at  any  place,  or  the  distance  of 
the  sun  from  the  zenith,  would,  in  the  case  supposed,  give 
the  observer  the  latitude  of  that  place. 

If  we  now  take  into  account  the  sun’s  declination,  it 
will  increase  or  diminish  its  meridian  altitude,  according  as 
it  passes  north  or  south  of  the  equator  ; but  the  declination 
of  the  sun  at  any  time  being  known,  its  zenith  distance, 
and  therefore  the  latitude  of  the  place,  can  be  readily 
ascertained  by  an  observation  made  when  the  sun  is  on  the 
meridian.  It  is  by  this  method  that  we  obtain  the  latitude 
of  any  place  by  the  Solar  Compass. 

A solar  day  is  the  interval  of  time  between  the  de- 
parture of  the  sun  from  the  meridian  of  a place,  and  its 
succeeding  return  to  the  same  position.  The 
length  of  the  solar  day,  by  reason  of  the  inclina- 
tion of  the  earth’s  axis,  is  constantly  changing. 

In  order  to  have  a uniform  measure  of  time,  we  have 
mean  solar  recourse  to  what  is  termed  a mean  solar 

day.  day,  the  length  of  which  is  equal  to  the 

mean  or  average  of  all  the  solar  days  in  a year. 

The  time  thus  given  is  called  mean  solar  time , and  is 
mean  SOLAR  same  at  anY  instant  for  all  points  on 

time.  the  same  meridian,  differing,  however,  at 

points  on  different  meridians. 

Since  November,  1883,  in  the  United  States,  the 
mean  solar  lime  of  the  meridians  60°,  75Q,  90°,  105°  and 
standard  120°  west  of  Greenwich  are  adopted  as 
time.  standard  time , and  are  called  respectively 
Colonial,  Eastern,  Central,  Mountain,  and  Pacific  time. 
Each  differs  from  the  next  in  time  by  one  hour.  In- 
stead of  employing  the  local  mean  solar  time , the  time  used 
is  the  mean  solar  time  at  the  nearest  of  the  standard 
meridians. 


ASTRONOMICAL  TERMS. 


93 


At  Troy,  N.  Y.,  the  longitude  is  73°  40'  west,  or  four 
hours,  fifty-four  minutes  and  forty  seconds  ; hence  the 
mean  solar  time  is  five  minutes  and  twenty  seconds  later 
than  the  standard  time.  At  Minneapolis  the  longitude  is 
six  hours,  twelve  minutes  and  fifty-seven  seconds  ; hence 
the  mean  solar  time  is  twelve  minutes  and  fifty-seven 
seconds  earlier  than  standard  time , since  the  city  is  west  of 
the  meridian. 


EQUATION  OF 


The  sun  is  sometimes  faster  and  some- 
TIME-  times  slower  than  the  clock,  the  difference 

being  called  the  eqitation  of  time. 

The  moment  when  the  sun  is  on  the  meridian  of  any 
place  is  called  apparent  noon , and  this  being  ascertained, 
apparent  we  can>  fry  adding  the  equation  of  time  for  the 

noon.  given  day  to,  or  subtracting  from,  apparent 

noon,  according  as  the  sun  is  slow  or  fast,  obtain  the  time 
of  mean  noon , which,  converted  to  standard  time , is  used  to 
set  the  watch  or  chronometer. 

As  the  earth  makes  a complete  rotation  upon  its  axis 
once  a day,  every  point  on  its  surface  must  pass  over  three 
difference  OF  hundred  and  sixty  degrees  in  twenty- 
longitu de.  four  hours,  or  fifteen  degrees  in  one 
hour,  and  so  on  in  the  same  ratio.  And  as  the  rotation  is 
from  west  to  east,  the  sun  would  come  to  the  meridian  of 
every  place  fifteen  degrees  west  of  Greenwich  just  one 
hour  later  than  the  time  given  in*the  Ephemeris  for 
apparent  noon  at  that  place. 

To  an  observer  situated  at  Troy,  N.  Y.,  the  longitude 
of  which  is,  in  time,  four  hours,  fifty-four  minutes,  forty 
seconds,  the  sun  would  come  to  the  meridian  nearly  five 
hours  later  than  at  Greenwich,  and  thus  when  it  was 
12  M.  at  that  place  it  would  be  but  about  7 A,  M,  in 
Troy. 


94 


ASTRONOMICAL  TERM$. 


By  reason  of  the  atmosphere,  the  rays  of  light  from  the 
sun  are  kent  out  of  their  course,  so  as  to 
make  its  altitude  appear  greater  than  is 
actually  the  case. 

The  amount  of  refraction  varies  according  to  the  alti- 
tude of  the  body  observed  ; being  0 when  it  is  in  the 
zenith,  about  one  minute  when  midway  from  the  zenith  to 
the  horizon,  and  almost  thirty-four  minutes  when  in  the 
horizon. 

There  is  a continual  change  of  the  place  of  the  sun’s 
image  between  the  equatorial  lines  (which  are  the  only 
EFFECT  OF  transit  lines  to  be  regarded  in  surveying 
refraction.  with  the  Solar),  not  only  with  the  change 
of  latitude,  but  also  with  the  change  of  the  sun’s  declina- 
tion from  hour  to  hour,  marked  by  the  motion  of  the  re- 
volving arm  as  it  follows  the  sun  in  its  daily  revolution. 

If  the  equatorial  lines  were  always  in  the  same  vertical 
plane  with  the  sun,  as  would  be  the  case  at  the  equator  at 
the  time  of  the  equinoxes,  it  is  evident  that  refraction 
would  have  no  effect  upon  the  position  of  the  image  be- 
tween these  lines,  and  therefore  would  not  be  of  any 
importance  to  the  surveyor. 

But  as  we  proceed  farther  north,  and  as  the  sun’s 
declination  to  the  south  increases,  the  refraction  also  in- 
creases, and  must  now  be  taken  into  account. 

. # 

Again,  the  angle  which  the  equatorial  lines  make  with 
the  horizon  is  continually  changing,  as  the  arm  is  made  to 
follow  the  motion  of  the  sun  during  the  course  of  a day. 

Thus,  in  the  morning  and  evening  they  are  more  or  less 
inclined  to  the  horizon,  while  at  noon  they  are  exactly 
parallel  with  it.  And  thus  it  follows  that  the  excess  of 
refraction  at  morning  and  evening  is  in  some  measure 
balanced  by  the  fact  that  the  position  of  the  sun’s  image 


A S TR  O NO  MICA  L TERMS. 


95 


with  reference  to  the  equatorial  lines  is  then  less  affected 
by  it,  on  account  of  the  greater  inclination  of  the  lines  to 
the  horizon. 

The  proper  allowance  to  be  made  for  refraction  in  set- 
ting off  the  declination  is  explained  fully  on  pages  70-76. 


SURVEYORS’  COMPASSES. 


SOLAR  COMPASS. 
RAILROAD  COMPASS. 
VERNIER  COMPASS. 
PLAIN  COMPASS. 


Attachments  for  Compasses. 

COMPOUND  BALL-SPINDLE. 

LEVELING-ADOPTER. 

LEVELING-HEAD. 

TELESCOPIC  SIGHT. 


THE  SOLAR  COMPASS. 


HIS  instrument,  so  ingeniously  contrived  for  readily 


determining  a true  meridian,  or  north  and  south  line, 
was  invented  by  William  A.  Burt,  of  Michigan,  and 
patented  by  him  in  1836.  It  came  into  general  use  in  the 
surveys  of  the  U.  S.  public  lands,  the  principal  lines  of 
which  are  required  to  be  run  with  reference  to  the  true 
meridian. 

The  invention  long  since  became  public  property,  and 
for  nearly  fifty  years  the  Solar  Compass  has  been  manu- 
factured by  us,  with  improvements  of  our  own,  which  have 
made  it  increasingly  popular  and  efficient. 

The  arrangement  of  its  sockets  and  plates  is  similar  to 
that  of  the  Surveyor’s  Transit,  as  shown  on  page  34,  except 
that  the  sight-vanes  are  attached  to  the  under  plate  or 
limb,  and  this  revolves  around  the  upper  or  vernier  plate 
on  which  the  solar  apparatus  is  placed. 

The  limb  is  graduated  to  half  degrees,  is  figured  in  two 
rows,  0 to  360  and  0 to  90  each  way,  and  reads  by  the  two 
opposite  verniers  to  single  minutes. 

The  graduations  of  the  limb  and  all  other  arcs  of  the 
Solar  Compass  are  made  upon  sterling  silver. 


The  solar  apparatus  is  seen  in  the  place  of  the  needle, 
and,  in  fact,  operates  as  its  substitute  in  the  field. 

It  consists  mainly  of  three  arcs  of  circles,  by  which 
can  be  set  off  the  latitude  of  a place,  the  declination  of  the 
sun,  and  the  hour  of  the  day. 


THE  SOLAR  APPARATUS. 


97 


98 


SOLAR  COMPASS. 


TO  ADJUST  THE  SOLAR  COMPASS. 

The  adjustments  of  this  instrument  with  which  the  sur- 
veyor will  need  to  be  familiar  are  simple  and  few  in  number, 
and  will  now  be  mentioned  in  order. 

(1)  To  adjust  the  levels  : Proceed  as  directed  in  the 

account  of  the  other  instruments  we  have  described,  by 
bringing  the  bubbles  into  the  middle  of  the  tubes  by  the 
leveling-screws,  and  then  reversing  the  instrument  upon  its 
spindle  and  raising  or  lowering  the  ends  of  the  tubes,  until 
the  bubbles  will  remain  in  the  middle  during  a complete 
revolution  of  the  instrument. 

(2)  To  adjust  the  Equatorial  Lines  and  Solar  Lenses  : 
Same  as  page  85. 

(3)  To  adjust  the  Vernier  of  the  Declination  Arc  : 
Same  as  page  86. 

(4)  To  adjust  the  Solar  Apparatus  to  the  Compass- 

* Sights  : First  level  the  instrument,  and  with  the  clamp  and 

tangent  screws  set  the  main  plate  at  ninety  degrees  by  the 
verniers  and  horizontal  limb.  Then  remove  the  clamp  and 
tangent  screws,  and  raise  the  latitude  arc  until  the  polar  axis 
is  by  estimation  very  nearly  horizontal,  and,  if  necessary, 
tighten  the  screws  on  the  pivots  of  the  arc,  so  as  to  retain 
it  in  this  position. 

Fix  the  vernier  of  the  declination  arc  at  zero,  and  direct 
the  outside  edges  of  the  lens  blocks  to  some  distant  and 
well-marked  object,  and  observe  the  same  through  the  com- 
pass sights.  If  the  same  object  is  seen  by  both  observa- 
tions, and  the  verniers  read  to  ninety  degrees  on  the  limb, 
the  adjustment  is  complete  ; if  not,  the  correction  must  be 
made  by  moving  the  compass-sights  or  changing  the  posi- 
tion of  the  verniers. 

It  should  be  remarked  that  as  the  solar  work  is  attached 
permanently  to  the  sockets,  and  this  adjustment  made  by 


SOLAR  COMPASS. 


99 


NO.  210. 


Price  as  shown,  including  leveling-screws  and  clamp  and  tangent  to  spindle,  and 
with  tripod,  $210.00. 


100 


SOLAR  COMPASS. 


the  maker,  it  will  need  no  further  attention  at  the  hands  of 
the  surveyor  except  in  case  of  serious  accident. 

The  other  adjustments  are,  of  course,  also  made  in  the 
process  of  finishing  the  instrument,  and  are  liable  to  very 
little  derangement  in  the  ordinary  use  of  the  Solar 
Compass. 

This  instrument  should  always  be  used  on  a 

TR I PO  D 

tripod,  with  screws  for  ready  and  accurate  level- 
ing, and  a tangent  screw  for  directing  it  to  any  desired 
point. 

For  this  purpose  a leveling -head  with  tangent  screw, 
similar  to  those  shown  in  the  cut  of  the  Surveyors’  Transit, 
is  furnished  with  every  instrument. 

TO  RUN  LINES  WITH  THE  SOLAR  COMPASS. 

Having  set  off  in  the  manner  described  the  latitude  and 
declination  upon  their  respective  arcs,  the  instrument  being 
also  in  adjustment,  the  surveyor  is  ready  to  run  lines  by 
the  sun. 

To  do  this,  the  instrument  is  set  over  the  station  and 
carefully  leveled,  the  plates  clamped  at  zero  on  the  hori- 
zontal limb,  and  the  sights  directed  north  and  south,  the 
direction  being  approximately  given,  when  unknown,  by 
the  needle. 

The  solar  lens  is  then  turned  to  the  sun,  and,  with  one 
hand  on  the  instrument  and  the  other  on  the  revolving 
true  arm,  both  are  moved  from  side  to  side,  until 
meridian,  the  sun’s  image  is  made  to  appear  on  the 
silver  plate.  By  carefully  continuing  this  operation  the 
image  may  be  brought  precisely  between  the  equatorial 
lines.  The  line  of  sights  will  indicate  the  true  meridian, 
and  the  observation  may  now  be  made  ,and  the  flagman 
be  put  in  position. 

ii 


SOLAR  COMPASS. 


101 


When  a due  east  and  west  line  is  to  be  run,  the  verniers 
of  the  horizontal  limb  are  set  at  ninety  degrees,  and  the 
sun’s  image  kept  between  the  lines,  as  before. 

The  Solar  Compass  being  so  constructed  that  when  the 
sun’s  image  is  in  position  the  limb  must  be  clamped  at  zero 
in  order  to  run  a true  meridian  line,  it  will  be  evident  that 
the  bearing  of  any  line  from  the  meridian  may  be  read  by 
the  verniers  of  the  limb  precisely  as  in  the  ordinary  mag- 
netic needle  Compass  the  bearing  of  lines  is  read  from  the 
ends  of  the  needle. 

In  running  lines  the  magnetic  needle  may  be  kept  with 
the  sun  ; that  is,  the  point  of  the  needle  is  made  to  indicate 

use  of  zero  on  arc  compass-box,  by 

THE  needle,  turning  the  tangent  screw  connected  with 
its  arm  on  the  opposite  side  of  the  plate.  By  this  means 
the  lines  can  be  run  by  the  needle  alone  in  case  of  the 
temporary  disappearance  of  the  sun  ; but,  of  course,  in  such 
instances,  the  surveyor  must  be  sure  that  there  is  no  local 
attraction.  The  variation  of  the  needle,  which  is  noted 
at  every  station,  is  read  off  on  the  arc  by  the  vernier  on 
the  arm  of  the  needle-box. 

In  using  the  Compass,  if  the  revolving  arm  be  turned  a 
little  to  one  side  of  its  proper  position,  a false  or  reflected 
image  of  the  sun  will  appear  on  the 
silver  plate  in  nearly  the  same  place 
as  that  occupied  by  the  true  one.  It  is  caused  by  the  re- 
flection of  the  true  image  from  the  surface  of  the  arm,  and 
is  a fruitful  source  of  error  to  the  inexperienced  surveyor. 
It  can,  however,  be  readily  distinguished  from  the  real 
image  by  being  much  less  bright,  and  not  so  clearly 
defined. 

When  the  bearings  of  lines,  such  as  the  course  of  a 
stream  or  the  boundaries  of  a forest,  are  not  desired  with 


FALSE  IMAGE. 


102 


SOLAR  COMPASS. 


the  certainty  given  by  the  verniers  and  the  horizontal  limb, 
a rough  approximation  of  the  angle  which  they  make 
approximate  t^ie  true  meridian  is  obtained  by 

bearings.  the  graduations  on  the  outside  of  the 
circular  plate.  In  this  operation,  a pencil  or  thin  straight- 
edge of  any  kind  is  held  perpendicularly  against  the  circular 
edge  of  the  plate,  and  moved  around  until  it  is  in  range 
with  the  eye,  the  brass  center-pin,  and  the  object  observed. 
The  bearing  of  the  line  is  then  read  off  at  the  point  where 
the  pencil  is  placed. 


SUPERIORITY  OF  OUR  SOLAR  COMPASSES. 

The  Solar  Compass  as  first  made,  though  planned  with 
great  ingenuity  in  its  general  arrangement,  was  still  ex- 
tremely rude  in  its  mechanical  details  and  adjustments. 

The  points  in  which  we  claim  the  superiority  of  our 
Solar  Compass  over  any  other  manufactured,  and  by  means 
of  which  the  defects  just  mentioned  are  entirely  removed, 
are  partially  shown  in  the  various  cuts  already  given,  and 
will  now  be  stated  in  detail. 

1.  A motion  of  the  horizontal  plates  entirely  free  from  friction,  com- 
bined with  perfect  rigidity. 

2.  A tangent  movement  to  the  limb,  as  shown  under  the  plate. 

3.  A tangent  movement  with  clamp  to  the  declination  arc. 

4.  A tangent  movement  with  clamp  to  the  latitude  arc. 

5.  A tangent  movement  for  the  whole  instrument  about  its  socket. 

6.  Increased  facility  of  adjustment,  and  therefore  an  important  saving 
of  time. 


WEIGHT. 


The  Solar  Compass  with  leveling-head, 
but  without  tripod,  weighs  about  fifteen 
pounds. 


THE  RAILROAD  COMPASS. 


HE  ordinary  Compass  is  used  in  surveys  where  great 


accuracy  is  not  required,  and  where  land  is  abundant 
and  cheap.  It  is  very  difficult,  however,  to  measure  hori- 
zontal angles  accurately  and  minutely  by  the  needle  alone  ; 
and  in  some  localities  needle-instruments  are  considered 
so  untrustworthy  that  Land  Surveyors  are  forbidden  to  use 
an  instrument  unless  it  is  capable  of  taking  angles  inde- 
pendently of  the  needle. 

To  meet  the  demand  for  more  accurate  work  than  can 
be  done  with  the  ordinary  Compass,  the  Railroad  Compass 


AND  limb.  pass  of  the  highest  grade,  with  a graduated 
limb  and  verniers  like  those  of  the  Transit.  It  has,  as  shown 
on  page  104,  the  main  plate,  levels,  sights,  and  needle  of  the 
ordinary  instrument,  and,  in  addition,  underneath  the  main 
plate,  a graduated  circle  or  limb  by  which  horizontal  angles 
to  single  minutes  can  be  taken  independently  of  the  needle. 

The  limb  is  figured  in  two  rows,  0 to  360  and  0 to  90 
each  way. 

The  arrangement  of  the  sockets  is  like  that  of  the  Sur- 


in  the  same  manner. 

The  sockets  upon  which  the  plates  of  this  instrument  turn 
are  long  and  well-fitted  and  the  movement  of  the  vernier 


The  verniers  are  attached  to  the  under  surface  of  the 


they  are  seen  being  covered  with  glass  to  protect  the  gradua- 
tions from  dust  and  moisture. 


PLATES 


has  been  devised.  This  instrument  is  a Com- 


SOCKETS. 


veyors’  Transit  with  two  verniers  to  limb, 
and  the  plates  can  be  separated  and  replaced 


plate  around  the  limb  is  almost  entirely  free  from  friction. 


VERNIERS. 


main  plate  at  an  angle  of  thirty  degrees  with 
the  line  of  sights,  the  openings  through  which 


103 


104 


RAILROAD  COMPASS. 


Railroad  Compass,  with  two  verniers  to  limb,  5%-inch  needle  and  staff  mountings. 

Price,  $75.00. 


RAILROAD  COMPASS. 


105 


The  connection  between  the  two  plates  is  made  by  a 
clamp  and  tangent  movement  with  opposing  spring,  shown 
at  t underneath  the  plates. 

The  needle-lifting  screw  is  shown  at  n,  on  the  left  of  the 
plate.  On  the  right  of  the  Compass-circle  is  seen  the  head 
of  a pinion  working  into  a rack  fixed  to  the  edge  of  the 
compass-circle,  thus  enabling  the  surveyor  to  move  the 
compass-circle  about  its  center  in  setting  off  the  variation 
of  the  needle,  as  in  the  case  of  the  Vernier  Compass. 

The  variation  is  read  to  single  minutes  by  a vernier 
and  graduated  arc,  partially  shown  in  the  cut. 

A clamp  screw  is  shown  at  c , by  which  the  circle  is 
securely  fixed  when  moved  to  the  proper  position.  » 

TO  USE  THE  RAILROAD  COMPASS. 

It  can  be  set  upon  the  common  ball-spindle  or,  still 
better,  upon  the  tangent  ball,  placed  either  in  a staff  socket, 
a compass  tripod,  or  the  leveling-adopter  and  tripod,  as 
shown  on  page  122. 

We  have  also  adapted  to  many  of  these  instruments  the 
leveling-head  wfith  the  clamp  and  tangent  movement  and 
tripod,  and  this  is  preferable  to  any  other  support.  (See 
page  123.) 

To  take  Horizontal  Angles  : First  level  the  plate  and 

set  the  limb  at  zero,  fix  the  sights  upon  one  of  the  objects 
horizontal  selected,  and  clamping  the  whole  instru- 
anqles.  ment  to  the  spindle,  unclamp  the  vernier 
plate  and  turn  it  with  the  hand  until  the  sights  are 
brought  nearly  upon  the  second  object ; then  clamp  to 
the  limb,  and  with  the  tangent  screw  fix  them  precisely 
upon  it. 


106 


RAILROAD  COMPASS. 


The  number  of  degrees  and  minutes  read  off  by  the 
vernier  will  give  the  angle  between  the  two  objects  taken 
from  the  center  of  the  instrument. 

It  will  be  understood  that  horizontal  angles  can  be 
taken  in  any  position  of  the  verniers  with  reference  to  the 
zero  point  of  the  limb  ; we  have  given  that  above  as  being 
the  usual  method,  and  liable  to  the  fewest  errors. 

Where  great  accuracy  is  required,  it  is  advisable,  in  this 
and  other  instruments  which  have  two  verniers,  to  obtain 
the  readings  of  the  limb  from  both,  add  the  two  together 
and  halve  their  sum  ; the  result  will  be  the  mean  of  the 
two  readings,  and  the  true  angle  between  the  points 
observed. 

Such  a course  is  especially  necessary  when  the  read- 
ings of  the  verniers  essentially  disagree,  as  may  sometime 
happen  when  the  instrument  has  been  injured  by  an 
accident. 

In  taking  horizontal  angles  as  just  described,  the  mag- 
netic bearings  of  the  two  objects  are  often  noted,  and  thus 
USE  QF  THE  two  separate  readings  of  the  same  angle, 
needle.  one  by  the  limb  and  the  other  by  the  needle, 
are  obtained,  to  be  used  as  checks  upon  each  other  to  pre- 
vent mistakes. 

To  turn  off  the  variation  of  the  needle  : Having 

leveled  the  instrument,  set  the  limb  at  zero  and  place  the 

magnetic  sights  upon  the  old  line,  note  the  reading 
variation,  of  the  needle,  and  make  it  agree  with  that 
given  in  the  field-notes  of  the  former  survey  by  turning  the 
compass-circle  about  its  center  by  the  pinion-head. 

Now  clamp  the  compass-circle,  and  the  number  of 
degrees  or  minutes  passed  over  by  the  vernier  of  the  com- 
pass-circle will  be  the  change  of  variation  in  the  interval 
between  the  two  surveys. 


RAILROAD  COMPASS . 


107 


To  survey  with  this  instrument,  the  operator  should 
turn  the  south  end  of  the  compass  towards  his  person, 
using  THE  anc*  having  brought  the  zeros  of  the  limb 
compass,  and  vernier  plate  in  line,  clamp  them,  and 
proceed  as  directed  in  our  account  of  the  Vernier  Compass. 

The  Telescopic  Sight,  as  hereafter  described,  is  often 
used  with  the  Railroad  Compass  with  excellent  results. 

It  will  be  understood  that  lines  can  be  run  and  angles 
measured  by  the  graduated  limb  and  verniers,  independently 
of  the  needle  ; and  in  places  where  local  attraction  is  mani- 
fested this  is  very  desirable. 

The  accuracy  and  minuteness  of  horizontal  angles  indi- 
cated by  this  instrument,  together  with  its  perfect  adapta- 
tion to  all  the  purposes  for  which  the  Vernier  Compass  can 
be  used,  have  brought  it  into  use  in  many  localities  where 
land  is  so  valuable  as  to  require  more  careful  surveys  than 
are  practicable  with  a needle-instrument. 

Size  and  Weight  of  the  Railroad  Compass  with  two 
Verniers:  We  make  two  sizes  of  this  instrument,  viz.: 

size  and  ^ve  and  five  and  one-half-inch  needles  ; 

weight.  the  smaller  size,  including  the  brass  head  of 
the  staff,  weighs  thirteen  pounds,  and  the  instrument  with 
five  and  one-half-inch  needle  weighs  about  fourteen  pounds. 

RAILROAD  COMPASS , ONE  VERNIER  TO  LIMB . 

This  instrument  is  essentially  like  that  already  described, 
but  of  somewhat  simpler  construction  in  its  sockets  ; and, 
though  offered  at  a price  materially  lower  than  the  other, 
it  is  in  every  way  accurate  and  reliable. 

Size  and  Weight  of  the  Railroad  Compass  with  one 
vernier  : We  make  but  one  size  of  this  instrument,  with 

five  and  one-half-inch  needle,  which  weighs  about  thirteen 
pounds. 


THE  VERNIER  COMPASS. 


" | ''HIS  instrument,  shown  on  page  110,  has  its  compass- 
^ circle,  to  which  is  attached  a vernier,  movable  about 
its  center  a short  distance  in  either  direction,  enabling  the 
surveyor  to  set  the  zeros  of  the  circle  at  any  required 
angle  with  the  line  of  sights.  The  number  of  degrees 
contained  in  this  angle  (or  the  variation  of  the  needle) 
is  read  off  by  the  vernier. 

The  Compass-Circle  in  this,  as  in  all  our  instruments,  is 
graduated  to  half  degrees  on  its  upper  surface,  the  whole 

degree  marks  being  also  cut  down 

COMPASS-CIRCLE.  , , . 

on  the  inside  circumference,  and  is 

figured  from  0 to  90  on  each  side  of  the  middle  or  line  of 
zeros.  The]  circle  and  face  of  the  Compass  are  silvered. 
The  movement  of  the  circle  is  effected  either  by  a tangent 
screw,  as  shown  in  the  cut,  or  by  a concealed  rack  and 
pinion,  the  head  of  which  projects  from  the  under  side  of 
the  main  compass-plate.  When  the  variation  is  set  off  as 
described,  the  circle  is  fastened  in  its  position  by  a clamp- 
screw. 

TJie  Compass  is  fitted  to  a spindle  made  slightly  conical, 
and  having  on  its  lower  end  a ball  turned  perfectly 

spherical,  and  confined  in  a socket 

BALL-SPINDLE.  u r , . „ 

by  a pressure  so  light  that  the  ball 

can  be  moved  in  any  direction  in  leveling  the  Compass. 
The  ball  is  placed  either  in  the  brass  head  of  the  staff  or, 
better,  in  the  compass  tripod  seen  in  the  cut  of  the  Vernier 
Transit  on  page  47. 

A leveling-adopter,  shown  on  page  122,  is  also  often 
used  for  more  convenient  leveling  of  the  Compass. 

108 


VERNIER  COMPASS. 


109 


LEVELS. 


SIGHTS. 


The  Staff  Mountings  consist  of  the  brass  head  already 
mentioned,  and  a pointed  steel  shoe.  The  staff,  to  which 
staff  the  mountings  should  be  securely  fas- 
mountings.  tened,  is  procured  from  any  wheelwright, 
or  selected  by  the  surveyor  himself  from  a sapling  of  the 
forest. 

The  Spirit-Levels  are  placed  at  right  angles  with  each 
other  so  as  to  level  the  plate  in  all  direc- 
tions, and  are  balanced  upon  a pivot  under 
the  middle  of  the  tube,  so  as  to  be  adjustable  by  a com- 
mon screw-driver. 

The  Sights,  or  sight-vanes,  have  fine  slits  cut  through 
nearly  their  whole  length,  terminated  at  intervals  by  circu- 
lar apertures,  through  which  the  object 
sighted  upon  is  more  readily  found.  Some- 
times a fine  horse-hair  or  wire  is  substituted  for  half  the 
slit,  and  placed  alternately  with  it  on  opposite  sights. 

The  Telescopic  Sight  is  often  supplied  with  the  Vernier 
Compass,  and  its  adjustments  and  use  are  described  on 
pages  124-130. 

The  right  and  left  edges  of  the  sights  of  our  Compasses 
have  respectively  an  eyepiece  and  a series  of  graduations,  by 
which  angles  of  elevation  and  depres- 
sion,-for  a range  of  about  twenty  degrees 
each  way,  can  be  taken  with  considerable  accuracy. 

This  arrangement  is  very  properly  called  a tangent 
scale,  the  graduated  edges  of  the  north  sight  being  tangents 
to  segments  of  circles  having  their  centers  at  the  eyepieces, 
and  their  points  of  contact  with  the  tangent  lines  at  the 
zero  graduations  of  the  scale. 

The  cut  shows  the  eyepiece  and  graduations  for  angles 
of  elevation  ; those  for  angles  of  depression,  not  shown  in 
this  cut,  are  seen  in  the  cut  of  the  Plain  Compass. 


TANGENT  SCALE. 


110 


VERNIER  COMPASS. 


Vernier  Compass,  6-inch  needle,  with  staff  mountings 
Price,  $40.00, 


VERNIER  COMPASS. 


Ill 


SPRING-CATCH. 


NEEDLE-LIFTER. 


In  the  side  of  the  hollow  socket  of  the  Compass,  which 

fits  to  the  ball-spindle,  is  a screw  bv 

CLAMP-SCREW.  1 * J 

which  the  instrument  may  be  clamped 
to  the  spindle  in  any  position. 

Besides  the  clamp-screw  there  is  fitted  to  the  sockets 
of  our  Compasses  a little  spring-catch, 
which,  as  soon  as  the  instrument  is  set 
upon  its  spindle,  slips  into  a groove,  and  thus  removes  all 
danger  of  the  instrument  falling  off  the  spindle  while  being 
carried. 

There  is  underneath  the  main  plate  a needle-lifting 
screw  which,  by  moving  a concealed 
spring,  raises  the  needle  from  the  pivot 
and  thus  prevents  the  blunting  of  the  point  in  transportation. 

When  the  Compass  is  not  in  use,  it  is  the  practice  of 
many  surveyors  to  let  down  the  needle  upon  the  point  of 
the  cepter-pin  and  let  it  assume  its  position  in  the  magnetic 
meridian,  so  as  to  retain  its  polarity.  We  would  advise 
that  after  the  needle  has  settled  it  should  be  raised  against 
the  glass,  in  order  not  to  dull  the  point  of  the  center-pin. 

A small  dial-plate,  having  an  index  turned  by  a milled 
head  underneath,  is  used  with  this  and  other 
outkeeper.  Compasses  to  keep  tally  in  chaining.  The 
dial  is  figured  from  0 to  16,  the  index  being  moved  one 
notch  for  every  chain  run. 

A brass  cover  is  fitted  over  the  glass  of 
the  Compass,  and  serves  to  protect  it  from 
accident,  as  well  as  to  prevent  electric  disturbance. 

The  superiority  of  the  Vernier  over  the  Plain  Compass 
use  of  consists  in  its  adaptation  to  retracing  the 
the  vernier,  lines  of  an  old  survey,  and  to  the  surveys 
of  the  U.  S.  public  lands,  where  the  lines  are  based  on  a 
true  meridian. 


BRASS  COVER. 


112 


VERNIER  COMPASS. 


It  is  well, known  that  the  magnetic  needle  in  almost  all 
parts  of  the  United  States  points  more  or  less  to  the  east 
variation  of  or  west  of  a true  meridian,  or  north  and 
the  needle,  south  line.  This  deviation,  which  is 
called  the  variation  of  the  needle,  is  not  constant,  but  increases 
or  decreases  to  a very  sensible  amount  in  a series  of 
years. 

Thus  at  Troy,  N.  Y.,  a line  bearing  in  1871,  N.  31°  E., 
would  in  1901,  with  the  same  needle,  have  a bearing  of 
about  N.  32°  49'  E.,  the  needle  having  thus  in  that  interval 
traveled  nearly  1°  49'  to  the  west. 

For  this  reason,  in  running  over  the  lines  of  a farm  from 
field-notes  of  some  years'  standing,  the  surveyor  is  obliged 
to  make  an  allowance,  both  perplexing  and  uncertain,  in 
the  bearing  of  every  line.  To  avoid  this  difficulty  the 
Vernier  Compass  was  devised. 

The  Vernier  is  graduated  on  its  edge  into 

VERNIER 

thirty  equal  parts,  and  figured  in  two  series  on 
each  side  of  the  middle  line. 

In  the  same  plane  with  the  vernier  is  an  arc  or  limb, 
fixed  to  the  main  plate  of  the  Compass,  and  graduated  to 
half  degrees. 

Each  space  on  the  vernier  is  one  minute  shorter  than  a 
single  space  on  the  limb. 

The  surfaces  of  both  vernier  and  limb  are  silvered. 

In  reading  the  vernier,  if  it  is  moved  to  the  right,  count 
the  minutes  from  its  zero  point  to  the  right,  and  vice  versa. 

to  read  Proceed  thus  until  a graduation  on  the 
the  vernier,  vernier  is  found  exactly  in  line  with 
another  on  the  limb,  and  the  lower  row  of  figures  on  the 
vernier  will  give  the  number  of  minutes  passed  over. 
When  the  vernier  is  moved  more  than  fifteen  minutes  to 
either  side,  the  number  of  additional  minutes,  up  to  thirty 


VERNIER  COMPASS . 


113 


or  one-half  degree  of  the  limb,  is  given  by  the  upper  row 
of  figures  on  the  opposite  side  of  the  vernier. 

To  read  beyond  thirty,  add  the  minutes  given  by  the 
vernier  to  that  number,  and  the  sum  will  be  the  correct 
reading. 

In  all  cases  when  the  zero-point  of  the  vernier  passes 
a whole  degree  of  the  limb,  this  must  be  added  to  the 
minutes,  in  order  to  define  the  distance  over  which  the 
vernier  has  been  moved. 

It  will  be  seen  that  the  surveyor  having  the  Vernier 
to  set  off  Compass  can,  by  moving  the  vernier  to 
the  variation,  either  side,  and  with  it,  of  course,  the 
compass-circle  attached,  set  the  Compass  to  any  varia- 
tion. 

He  therefore  places  his  instrument  on  some  well- 
defined  line  of  the  old  survey,  and  turns  the  tangent 
screw  until  the  needle  of  his  Compass  indicates  the  same 
bearing  as  that  given  in  the  field-notes  of  the  original 
survey. 

Then,  clamping  the  vernier,  he  can  run  all  the  other 
lines  from  the  old  field-notes  without  further  altera- 
tion. 

The  reading  of  the  vernier  on  the  limb  in  such  a case 
would  show  the  change  of  variation  of  the  two  different 
periods. 

The  variation  of  the  needle  at  any  place  being  known, 
a true  meridian,  or  north  and  south  line,  may  be  run  by 
moving  the  vernier  to  either  side,  as  the  variation  is  east 
or  west,  until  the  arc  passed  over  on  the  limb  is  equal  to 
the  angle  of  variation,  and  then  turning  the  Compass  until 
the  needle  is  made  to  cut  the  zeros  on  the  graduated  circle. 
The  line  of  sights  will  then  give  the  direction  of  the  true 
meridian  of  the  place. 


114 


VERNIER  CO  ME  ASS. 


Such  a change  in  the  position  of  the  vernier  is  neces- 
sary in  surveying  the  U.  S.  public  lands,  which  surveys  are 
always  run  from  the  true  meridian. 

The  line  of  no  declination,  or  variation,  as  it  is  called, 
or  the  line  upon  which  the  needle  will  indicate  a true  north 
line  of  NO  and  south  direction,  is  situated  in  the  United 
variation.  States  nearly  in  an  imaginary  line  drawn 
from  Sault  Ste.  Marie,  Michigan,  to  Charleston,  South 
Carolina.  A compass-needle,  therefore,  placed  east  of 
this  line,  has  a variation  to  the  ^yest,  and  when  placed 
west  of  the  line  the-  variation  is  to  the  east ; and  in  both 
cases  it  increases  as  the  needle  is  carried  farther  from  the 
line  of  no  variation. 

Thus,  in  Minnesota,  the  variation  is  from  eight  to 
eleven  degrees  to  the  east,  while  in  Maine  it  is  from  fifteen 
to  nineteen  degrees  to  the  west.  At  Troy,  in  the  present 
year,  1902,  the  variation  is  about  11°  09'  to  the  west,  and 
is  increasing  in  the  same  direction  about  two  minutes 
annually. 

The  variation  of  the  magnetic  needle  does  not  remain 
constant  through  an  entire  day  ; but  it  reaches  its  farthest 
diurnal  point  east  about  8 o’clock,  A.  M.,  and  its 
variation,  farthest  point  west  about  2 o’clock,  P.  M. 
The  cause  of  this  daily  variation  of  the  needle  is  not  under- 
stood, as  observations  show  that  it  is  greater  in  summer 
than  in  winter. 

Conditions  of  temperature,  magnetic  storms  and  other 
causes  at  times  affect  the  needle.  Our  own  experiments 
show  that  different  needles  observed  at  the  same  time  and 
under  the  same  conditions  differ  in  their  direction,  but 
show  nearly  the  same  daily  change. 

A less  important  use  of  the  vernier  is  to  give  a reading  of 
the  needle  to  single  minutes,  which  is  obtained  as  follows : 


VERNIER  COMPASS . 


115 


First  be  sure,  as  in  all  observations,  that  the  zero  of  the 
vernier  exactly  corresponds  with  that  of  the  limb  ; then, 
to  read  to  noting  the  number  of  the  whole  de- 
MINUTES.  grees  given  by  the  needle,  move  back 
the  compass-circle  with  the  tangent  screw  until  the  near- 
est whole  degree  mark  is  made  to  coincide  with  the  point 
of  the  needle,  read  the  vernier  as  before  described,  and 
this  reading  added  to  the  whole  degrees  will  give  the  bear- 
ing to  minutes. 


TO  ADJUST  THE  COMPASS. 

To  adjust  the  Levels  : First  bring  the  level-bubbles  into 
the  middle  by  the  pressure  of  the  hand  on  different  parts  of 
the  plate,  and  then  turn  the  Compass  half- 
way around  ; should  the  bubbles  run  to 
the  end  of  the  tubes,  it  would  indicate  that  those  ends 
were  the  highest ; lower  them  by  loosening  the  screws 
under  the  lowest  ends  and  tightening  those  under  the 
highest  ends  until,  by  estimation,  the  error  is  half  removed  ; 
level  the  plate  again,  and  repeat  the  first  operation  until  the 
bubbles  will  remain  in  the  middle  during  an  entire  revolu- 
tion of  the  Compass. 

The  sights  may  next  be  tested  by  observing  through 
the  slits  a fine  hair  or  thread,  made  exactly  vertical  by 
a plummet.  Should  the  hair  appear  on  the 
sight-vanes.  s^e  s|j^  the  sight  must  be  ad- 

justed by  filing  its  under  surface  on  the  side  which  seems 
the  highest. 

To  adjust  the  Needle  : Having  the  eye  nearly  in  the 

same  plane  with  the  graduated  rim  of  the 
NEEDLE.  r . . . , & lt 

compass-circle,  with  a small  splinter  of 

wood  or  a slender  iron  wire  bring  one  end  of  the  needle  in 


116 


VERNIER  COMPASS. 


line’with  any  prominent  graduation  of  the  circle,  as  the  zero 
or  the  ninety  degree  mark,  and  notice  if  the  other  end  cor- 
responds with  the  degree  on  the  opposite  side  ; if  it  does 
the  needle  is  said  to  “cut”  opposite  degrees  ; if  not,  bend 
the  center-pin  by  applying  a small  brass  wrench,  furnished 
with  our  Compasses,  about  one-eighth  of  an  inch  below  the 
point  of  the  pin,  until  the  ends  of  the  needle  are  brought 
into  line  with  the  opposite  degrees.  i 

Then,  holding  the  needle  in  the  same  position,  turn  the 
Compass  half-way  around,  and  note  whether  it  now  cuts 
opposite  degrees  ; if  not,  correct  half  the  error  by  bending 
the  needle,  and  the  remainder  by  bending  the  center-pin. 
The  operation  should  be  repeated  until  perfect  reversion  is 
secured  in  the  first  position. 

This  being  obtained,  it  may  be  tried  on  another 
quarter  of  the  circle  ; if  any  error  is  there  manifested, 
the  correction  must  be  made  in  the  center  - pin  only, 
the  needle  being  already  straightened  by  the  previous 
operation. 

When  again  made  to  cut,  it  should  be  tried  on  the 
other  quarters  of  the  circle,  and  corrections  made  in  the 
same  manner  until  the  error  is  entirely  removed,  and  the 
needle  will  reverse  in  every  point  of  the  graduated  surface. 

TO  USE  THE  COMPASS. 

In  using  the  Compass,  the  surveyor  should  keep  the 
south  end  towards  his  person,  and  read  the  bearings  from 
the  north  end  of  the  needle.  He  will  observe  that  the  E 
and  W letters  on  the  face  of  the  Compass  are  reversed 
from  their  natural  position,  in  order  that  the  direction  of 
the  line  of  sight  may  be  correctly  read. 

The  compass-circle  being  graduated  to  half  degrees,  a 
little  practice  will  enable  the  surveyor  to  read  the  bearings 


VERNIER  COMPASS. 


117 


to  quarter  degress  or  even  less,  estimating  with  his  eye  the 
space  bisected  by  the  point  of  the  needle  ; and  as  this  is  as 
close  as  the  traverse  table  is  usually  calculated,  it  is  the 
general  practice. 

Having  leveled  the  Compass,  bring  the  south  end 
towards  the  person,  and  place  the  eye  at  the  little  button, 
angles  of  or  eyepiece,  on  the  right  side  of  the  south 
elevation,  sight,  and  with  the  hand  hold  a card  on  the 
front  surface  of  the  north  sight,  so  that  its  top  edge  will  be 
at  right  angles  with  the  graduated  edge  and  coincide  with  the 
zero  mark.  Then,  sighting  over  the  top  of  the  card,  note 
upon  a flagstaff  the  height  cut  by  the  line  of  sight,  move 
the  staff  up  the  elevation,  and  carry  the  card  along  the 
sight  until  the  line  of  sight  again  cuts  the  same  height 
on  the  staff ; read  off  the  degrees  and  half  degrees 
passed  over  by  the  card,  and  this  will  be  the  angle 
required. 


angles  OF  Proceed  in  the  same  manner,  using  the 
depression,  eyepiece  and  graduations  on  the  opposite 
side  of  the  sight,  and  reading  from  the  top  of  the  sight. 
new  and  old  When  the  Compass  is  to  be  used  in 
surveys.  making  new  surveys,  the  vernier  should 
be  set  at  zero  and  clamped  by  the  nut  beneath  the  plate. 

In  surveying  old  lines,  the  change  of  variation  of  the 
needle  should  be  ascertained  by  setting  the  Compass  on 
some  well-defined  line  of  the  tract,  and  making  the  bearing 
to  agree  with  that  of  the  old  survey,  by  moving  the  circle 
as  already  described. 

Then  the  circle  can  be  clamped,  and  the  old  lines  re- 
traced from  the  bearings  given  by  the  original  surveyor. 

When  the  variation  of  the  needle  is  known,  it  can  be 
set  off  by  the  vernier,  and  the  Compass  used  to  run  a true 
meridian  by  the  needle. 


118 


VERNIER  COMPASS. 


A little  caution  is  necessary  in  handling  the  Compass, 
that  the  glass  covering  does  not  become  charged  with  elec- 
tricity excited  by  the  friction  of  cloth,  silk 

ELECTRICITY.  ~ . 

or  the  hand,  so  as  to  attract  the  needle  to 

its  under  surface.  When,  however,  the  glass  becomes  so 
charged,  the  electricity  may  be  removed  by  breathing  upon 
it,  or  by  touching  different  parts  of  its  surface  with  the 
moistened  finger.  Ignorance  of  this  apparently  trifling  mat- 
ter has  caused  many  errors  and  perplexities  in  the  practice 
of  the  inexperienced  surveyor. 

REPAIRS  OF  THE  COMPASS. 

To  enable  the  surveyor  to  make  such  repairs  as  are 
possible  without  having  recourse  to  an  instrument-maker, 
we  here  add  a few  simple  directions. 

It  may  sometimes  happen  that  the  needle  has 
lost  its  polarity  and  needs  to  be  remagnetized  ; 
to  do  this,  proceed  as  follows  : Unscrew  the  bezel-ring  that 
holds  the  glass  face,  remove  the  needle  and  pass  with  a gentle 
pressure  each  end  of  the  needle  from  middle  to  extremity 
over  the  magnetic  pole  of  an  ordinary  permanent  magnet, 
describing  before  each  pass  a circle  of  about  six  inches  ra- 
dius, to  which  the  surface  of  the  pole  is  tangent,  drawing  the 
needle  towards  him,  and  taking  care  that  the  north  and  the 
south  ends  are  applied  to  the  opposite  poles  of  the  magnet. 

Should  the  needle  be  returned  in  a path  near  the  mag- 
netic pole,  the  current  induced  by  the  contact  of  the  needle 
and  magnet,  in  the  pass  just  described,  would  be  reversed, 
and  thus  the  magnetic  virtue  almost  entirely  neutralized  at 
each  operation. 

When  the  needle  has  been  passed  about  twenty-five  times 
in  succession  in  the  manner  just  described  it  may  be  con- 
sidered as  fully  charged. 


VERNIER  COMPASS. 


119 


A fine  brass  wire  is  wound  in  two  or  three  coils  on  the 
south  end  of  the  needle,  and  may  be  moved  back  or  forth  in 
order  to  counterpoise  the  varying  weight  of  the  north  end. 

The  center-pin  should  occasionally  be  examined,  and  if 
much  dulled,  should  be  taken  out  with  the  brass  wrench  or 

with  a pair  of  pliers,  and  sharpened  on  a 

CENTER-PIN.  , ...f.  .f  ’ 

hard  oilstone,  the  operator  placing  it  in  the 

end  of  a small  stem  of  wood,  or  a pin-vise,  and  delicately 
twirling  it  with  the  fingers  as  he  moves  it  back  and  forth  at 
an  angle  of  about  thirty  degrees  with  the  surface  of  the  stone. 

When  the  point  is  thus  made  so  fine  and  sharp  as  to  be 
invisible  to  the  eye  it  should  be  smoothed  by  rubbing  it  on 
the  surface  of  a soft  and  clean  piece  of  leather. 

To  put  in  a new  glass  : Unscrew  the  bezel-ring  which 

holds  it,  and  with  the  point  of  a knife-blade  spring  out 
glass  the  little  brass  ring  above  the  glass  and  remove 
circle.  the  old  glass  and  scrape  out  the  putty.  Then,  if 
the  new  glass  does  not  fit,  smooth  off  its  edges  by  holding 
it  obliquely  on  the  surface  of  a grindstone  until  it  will  enter 
the  ring  easily  ; then  put  in  new  putty,  spring  in  the  brass 
ring,  and  the  operation  will  be  complete. 

To  replace  a level-vial  : Take  out  the  screws  which 

hold  it  to  the  plate,  pull  off  the  brass  ends  of 
the  tube,  and  with  a knife-blade  scrape  out 
the  plaster  from  the  tube.  Then  with  a stick  made  a little 
smaller  than  the  diameter  of  the  tube,  and  with  its  end 
hollowed  out  so  that  it  will  bear  only  on  the  broad  surface 
of  the  level-vial,  push  out  the  old  vial  and  replace  it  with 
a new  one,  taking  care  that  the  crowning  side,  which  has  a 
file-mark  on  the  end  of  the  vial,  is  placed  on  the  upper  side. 

When  the  vial  does  not  fit  the  tube,  it  must  be  wedged 
up  by  putting  little  slips  of  paper  under  it,  until  it  moves 
in  snugly. 


120 


VERNIER  COMPASS. 


After  the  vial  is  in  its  place,  put  around  its  end  a little 
plaster  of  Paris  mixed  with  water  to  the  consistency  of 
putty,  taking  care  not  to  allow  any  to  cover  the  little  tip  of 
the  glass,  then  slip  in  the  brass  ends,  and  the  operation  will 
be  complete. 

A little  beeswax,  melted  and  dropped  upon  the  ends  of 
the  vial,  is  equally  as  good  as  the  plaster  of  Paris,  and  often 
more  easily  obtained. 

An  extra  glass  and  level-vials  are  always  furnished,  free 
of  charge,  with  every  new  Compass. 

We  make  three  sizes  of  the  Vernier  Compass,  having 
needles  respectively  four,  five,  and  six  inches  long,  the  main 
plates  being  respectively  twelve  and  one-half, 
fifteen,  and  fifteen  and  one-half  inches  long. 
The  sights  of  the  smallest  are  also  about  an  inch  shorter 
than  the  others. 

In  the  four  and  five-inch  Vernier  Compasses,  the  varia- 
tion arc  is  within  the  compass-circle,  like  that  of  the  Rail- 
road Compass  before  described,  and  the  variation  is  set  off 
to  minutes  by  a pinion-head  underneath  the  plate,  and  this 
arc  is  clamped  by  a screw  placed  opposite  the  pinion. 

The  average  weights  of  the  different  sizes,  including  the 
brass  head  of  the  staff,  beginning  with  the 
smallest,  are  respectively  six  and  one-quar- 
ter, eight  and  three-quarters,  and  ten  and  one-half  pounds. 


SIZES 


WEIGHTS. 


Price,  with  6-inch  needle  and  staff  mountings,  $35.00. 


'TP  HE  Plain  Compass  shown  in  the  cut  has  a six-inch 
A needle,  and  is  furnished  with  levels,  sight-vanes, 
socket,  etc. 

The  compass-box  is  in  the  same  piece  with  the  main 
plate,  and  the  instrument  is  used  chiefly  in  the  surveys  of 
new  lines,  or  in  the  preparation  of  maps,  where  the  varia- 
tion of  the  needle  is  not  required. 

The  adjustments  and  use  of  the  Plain  Compass  are 
substantially  the  same  as  those  of  the  Vernier  Compass 
just  described. 

Three  sizes  of  this  instrument  are  in  common  use,  hav- 
ing respectively  four,  five  and  six-inch  needles, 

SIZES* 

and  differing  also  in  the  length  of  the  main  plate, 
which,  in  the  four-inch  Compass  is  twelve  and  one -half 


121 


122 


PLAIN  COMPASS. 


inches  long,  and  in  the  larger  sizes  fifteen  and  fifteen  and 
one-half  inches. 

The  average  weights  of  the  different  sizes, 
WEIGHT,  with  the  brass  mountings  of  the  staff,  are  as 
follows  : 


Plain  Compass  with  4-inch  needle 6 lbs. 

“ “ “ 5-inch  “ 7f  lbs. 

“ “ “ 6-inch  “ 9J  lbs. 


We  manufacture  a compound  ball-spindle,  which  has  a 
compound  tangent  movement,  and  which  gives  all 
ball-spindle,  the  perfection  of  more  costly  arrange- 
ments at  a very  moderate  expense.  The  price  is  $7.00. 

As  represented  in  the  cut,  No.  240,  it  has  an  interior 
spindle,  around  which  an  outside  hollow  cylinder  is 
moved  by  turning  the  double-headed  tangent  screw, 
which  has  in  the  middle  a screw,  working  into  teeth 

cut  spirally  around  the  cylinder. 
The  Compass  or  other  instru- 
ment revolves  on  the  outside 
socket,  exactly  as  if  placed  on 
a common  ball-spfndle  ; but  when 
a slower  movement  is  desired, 
it  can  be  clamped  and  then 
turned  gradually  around  the  in- 
terior spindle  by  the  tangent 
screw,  until  the  slit  of  the  sight 
or  the  intersection  of  the  wires 
is  made  to  bisect  the  object  with 
accuracy. 

For  more  convenient  leveling 

LEVELING-  t*ie  Compass,  as 

adopter.  well  as  other  instru- 

ments, we  make  the  appliance 


NO.  240. 


NO.  241 


PLAIN  COMPASS. 


123 


shown  in  No.  241,  which  is  screwed  to  the  top  of  the  tripod 
like  the  ordinary  leveling-head. 

This  can  be  used  either  with  a simple  ball-spindle,  or 
with  the  compound  ball  with  tangent  screw,  as  shown  in 
the  cut. 

The  instrument  is  made  approximately  level  upon  the 
ball,  and  finally  made  truly  horizontal  by  the  leveling- 
screws. 

The  price  of  the  leveling-adopter,  without  tripod  or 
ball-spindle,  is  $7.00  ; with  tripod  and  compound  tangent 
ball,  as  shown,  $19.00. 

We  also  make  for  use  with  Surveyors’  Compasses  and  Ver- 

leveling-  n*er  Transit- 
head.  Compasses  a 
leveling-head,  consisting 
of  upper  and  lower  plates, 
four  leveling-screws  and 
clamp  and  tangent  move- 
ment. (See  Price-List, 

Nos.  176  and  242.) 

This  leveling-head 
furnishes  a very  stable 
support  for  the  instru- 
ment, while  affording  the 
same  conveniences  for 
leveling  and  accurate  ad- 
justment in  azimuth  as 
the  leveling-heads  on  the 
more  expensive  instru- 
ments. 

The  price  complete  with  tripod,  and  fitted  to  the  socket 
of  the  Compass  or  Vernier  Transit,  is  $18.00,  or  without  the 
tripod,  $13.00. 


NOS.  176  AND  242. 

LEVELING-HEAD. 


THE  TELESCOPIC  SIGHT. 


We  have  for  years  applied  to  the  sight-vanes  of  Com- 
passes a telescope  which  can  be  put  on  and  removed  at 
will.  This  attachment  has  met  with  approval,  hundreds 
being  now  in  use  in  all  parts 
of  the  country. 

This  telescope  is  furnished 
with  the  usual  cross-wires,  and 
is  attached  to  a movable  band 
which,  as  shown  in  the  cut, 
can  be  slipped  over  the  sight 
of  a Compass,  clamped  at  any 
point  desired,  and  put  in  ad- 
justment by  any  person  who 
has  a screw-driver  and  a steel 
adjusting-pin.  To  put  this 
attachment  in  place,  slip  the 
band  over  the  south  sight  of 
the  Compass,  having  the  tele- 
scope at  the  right-hand  and 
the  clamp-screw  on  the  outer 
surface  of  the  sight ; and  place 
the  band  as  low  as  will  allow 
the  telescope  to  revolve  in 
either  direction  without  strik- 
ing the  Compass.  This  place 
should  be  marked  by  a line 
across  the  sight,  or  by  a screw 
or  pin  on  the  inner  surface  of  the  sight,  that  the  band  may 
set  at  the  same  point  in  subsequent  use, 

124 


Price  of  Telescope  No.  261  as  shown,  with 
movable  band  for  attaching,  $17.00. 


TELESCOPIC  SIGHT, 


125 


To  fasten  the  band  to  the  sight,  first  bring  up  the  clamp- 
screw  with -a  pressure  just  sufficient  to  hold  the  band  to  its 
place,  then  tighten  the  screw  on  the  left  until  the  band  is 
against  the  right  edge  of  the  sight,  and  finally  tighten  the 
clamp-screw  when  the  fastening  will  be  complete. 

To  put  the  telescope  in  focus,  turn  the  end  of  the  eye- 
piece back  or  forth  by  the  thumb  and  forefinger  until  by 
the  spiral  motion  of  the  tube  the  cross-wires  are  brought 
into  distinct  view  ; the  object-glass  is  then  moved  in  either 
direction  by  the  pinion  on  the  side  of  the  telescope  until  the 
object  is  clearly  seen. 

To  make  the  adjustments, 
and  indeed  to  do  any  correct 
work  with  a Compass,  the  spindle 

should  be  well- 

ADJUSTMENTS.  ~ 

fitted  and  the 

level-bubbles  should  remain  in 
the  middle  when  the  instrument 
is  turned  upon  its  spindle  ; the 
sights  should  also  trace  a vertical 
line  when  the  Compass  is  level. 

The  means  of  effecting  the 
adjustments  will  be  understood 
by  the  engraving  on  page  124 
and  the  outline  cut  here  given,  the  former  showing  the  rear, 
and  the  latter  the  front  view  of  the  band  to  which  the  tele- 
scope is  attached. 

To  make  the  telescope  axis  horizontal,  the  Compass 
being  in  good  ofder,  first  bring  the  levels  into  the  middle  ; 
telescope  place  the  band  in  position  upon  the  sight,  as 
axis.  before  described  ; bring  the  telescope  into 
focus  and  set  the  vertical  cross-wire  on  the  edge  of  a build- 
ing, distant  from  fifty  to  sixty  feet,  and  at  a point  near  the 


c 

p 

0 

-G 

* 

t 


126 


TELESCOPIC  SIGHT. 


ground  ; clamp  the  Compass  to  the  spindle,  and  raise  the 
telescope  to  the  top  of  the  building.  If  the  wire  strikes  to 
the  right  of  the  edge,  it  shows  that  the  right  end  of  the 
telescope  axis  is  the  lowest. 

To  raise  it,  loosen  the  screws,  B B,  C C,  which  confine 
the  piece  containing  the  spindle  of  the  telescope,  and  by 
the  screws,  D D,  the  lower  of  which  should  be  unscrewed 
and  the  upper  one  tightened,  raise  the  telescope  until  the 
wire  will  follow  the  vertical  line. 

If  the  cross-wire  strikes  to  the  left  when  the  telescope 
is  raised,  proceed  exactly  the  reverse  in  making  the  cor- 
rection, until  the  wire  will  follow  the  edge  from  one  end  to 
the  other,  when  the  adjustment  will  be  complete.  If  the 
vertical  cross-wire  is  not  parallel  with  the  edge,  loosen  the 
capstan-head  screws,  and  turn  the  ring  by  the  screw  heads 
until  the  correction  is  made  ; and  finally  tighten  the  screws. 

To  make  the  second  adjustment,  that  is,  to  bring  the 
line  of  collimation  into  a position  at  right  angles  with  the 
line  of  axis  of  the  telescope  so  that  the  cross- 
colli MAT! on.  wires  will  indicate  two  points  in  opposite 
directions  in  the  same  straight  line,  proceed  as  described 
on  pages  19-21. 

Find  or  place  two  objects,  one  on  each  side  of  the 
Compass,  and  from  three  hundred  to  four  hundred  feet 
distant  from  it,  which  the  sight-vanes  will  intersect.  Clamp 

adjustment  of  to  spindle  and  sight  through  the 
telescope  to  telescope  at  either  of  the  objects  ; if 

the  sights.  the  vertical  wire  strikes  to  the  right, 

loosen  the  screws,  B B,  and  screw  up  those  in  front, 
marked  F F,  the  ends  only  of  which  are  shown  in  the 
figure,  until  the  vertical  wire  bisects  the  object,  looking 
again  through  the  vanes  to  see  that  the  same  object  is 
seen  through  both  telescope  and  sights.  If,  however,  the 


TELESCOPIC  SIGHT. 


127 


cross-wire  should  strike  to  the  left  of  the  object,  proceed  in 
a manner  exactly  the  reverse  until  the  error  is  corrected. 

This  adjustment  is  always  made  by  us  before  the 
attachment  leaves  our  hands,  and  need  not  be  disturbed 
except  in  case  of  accident  or  careless  interference  with 
the  cross-wire  screws  ; but  it  can  be  easily  made  by  any 
surveyor  in  a few  moments  and  with  very  little  practice. 

When  the  adjustments  are  complete,  the  attachment 
can  be  put  in  place  on  the  sight,  and  removed  and  replaced 
again  in  a moment,  without  danger  of  derangement  in  any 
of  its  parts. 

The  advantage  of  the  telescope  over  the  ordinary  sight- 
vanes  will  be  apparent  to  every  one  who  has  ever  seen  them 
compared,  or  who  has  given  the  matter  a moment’s  reflection. 

Much  longer  sights  can  be  taken,  either  fore  or  back, 
and  lines  run  up  and  down  steep  hillsides  with  the  same 
facility  as  on  level  ground,  and  with  more  accuracy  and 
with  inexpressible  relief  to  the  eyes  of  the  .surveyor,  so 
often  severely  strained  by  the  use  of  the  sight-vanes  of  the 
ordinary  Compass.  Indeed  it  may  be  said  that  with  this 
simple  attachment  every  Compass  can  be  transformed  into 
a Transit-Compass  at  will,  and  thus  all  the  advantages  of 
the  telescope  brought  within  the  reach  of  every  surveyor, 
at  comparatively  trifling  cost. 

The  optical  axis  of  the  Telescopic  Sight  is  at  one  side 
of  the  line  of  sight  of  the  sight-vanes,  but  parallel  with 

it.  The  difference  between  a sight  taken 

OPTICAL  AXIS.  . , , 

with  the  sight-vanes  and  one  taken  with 
the  telescope  is,  at  a distance  of  two  hundred  feet,  about  two 
minutes  ; so  small  that  it  may  be  disregarded  in  any  survey 
made  with  the  magnetic  needle.  If  all  the  lines  are  run 
with  the  Telescopic  Sight,  the  angles  measured  will  be 
accurate,  as  even  this  slight  difference  is  entirely  eliminated. 


128 


TELESCOPIC  SIGHT. 


When  desired,  the  Telescopic  Sight  can  be  mounted  upon 
OFFSET-  an  offset-standard  with  counterpoise,  and  so 
standard,  arranged  that  the  line  of  sight  is  in  line  with 
the  zeros  of  the  compass-circle. 

When  in  use,  this  standard,  with  the  telescope  attached 
to  it,  is  substituted  for  the  south  sight  of  the  Compass. 

The  extra  cost  of  this  offset-standard  with  counterpoise 
is  $7.50. 

When  furnished  with  a new  instrument  the  telescope  is 
packed  in  the  box  with  the  Compass,  or  it  can  be  safely  for- 
warded by  mail  to  any  part  of  the  country,  securely  packed 
in  a suitable  case  in  which  it  may  be  kept  when  not  in  use. 


TELESCOPIC  SIGHT. 


129 


We  make  three  styles  of  the 
SIZES  AND  POWER.  Telescopic  sight,  numbered  260,  261, 

and  262  in  the  price-list. 

In  No.  260,  the  telescope  is  about  nine  inches  long,  is 
fitted  with  plain  cross-wires,  and  has  a power  of  twelve 
diameters. 

Nos.  261  and  262  have  a power  of  eighteen  to  twenty 
diameters,  and  the  telescopes  are  about  nine  inches  long  ; 
but  the  telescope  of  No.  262  has  a greater  diameter,  allow- 
ing the  insertion  of  stadia  wires,  in  addition  to  the  ordinary 
cross-wires  used  in  the  other  telescopes. 

The  extras  of  vertical  circle  three  inches  in  diameter 
and  reading  to  five  minutes,  level  on  telescope  with  gradu- 
extra  ated  vial,  and  clamp  and  tangent  to  axis, 

attachments,  may  be  used  with  either  of  these  Tele- 
scopic Sights.  Whenever  the  level  is  used,  it  is  necessary 
that  the  clamp  and  tangent  to  axis  be  added. 

In  the  cut  on  page  128  the  Telescope  No.  262  is  shown 
fitted  with  a level  and  clamp  and  tangent.  For  simple 
sighting  the  level  and  circle  can,  of  course,  be  dispensed 
with,  but  in  the  use  of  the  stadia  wires  the  tangent  move- 
ment is  very  desirable. 

When  measurements  are  to  be  recorded  in  chains 
and  links,  the  stadia  wires  should  be  made  to  cover  one 
foot  at  a distance  of  sixty-six  feet  ; if  recorded  in  feet, 
the  wires  should  cover  one  foot  at  a distance  of  one 
hundred  feet. 

The  rod  used  with  the  stadia  should  be  graduated  to 
feet  and  decimals  of  a foot  and  provided  with  two  targets, 
one  being  fixed  at  some  definite  point,  while  the  other 
one  can  be  moved  as  the  surveyor  requires,  the  distance 
between  the  two  targets  being  accurately  read  off  by 
the  vernier  of  the  movable  one  ; or  a self-reading  rod,  as 


130 


TELESCOPIC  SIGHT 


described  on  pages  188  and  190,  may  be  used  without  tar- 
get for  short  distances. 

In  using  the  stadia,  the  upper  wire  is  brought  by  the 
tangent  screw  precisely  upon  the  upper  or  stationary  target, 
while  the  lower  target  is  moved  up  or  down  until  the  lower 
wire  exactly  bisects  its  center  line,  when  the  rod  is  read 
and  the  distance  recorded. 

PRICES  OF  TELESCOPIC  SIGHTS  AND  ATTACHMENTS. 


No.  , Price.  Post. 

260.  Nine -inch  Achromatic  Telescope,  power  about 

twelve  diameters $15.00  $0.45 

261.  Nine -inch  Achromatic  Telescope,  larger  diameter  of 

object-glass  and  power  about  20  diameters 17.00  .45 

262.  Same  Telescope  as  No.  261,  but  furnished  with 

stadia  wires  for  measuring  distances 20.00  .50 


We  add  to  these  Telescopic  Sights  the  following  extras, 
at  prices  annexed. 


265.  Vertical  Circle  with  vernier  to  five  minutes $5.00 

266.  Level  on  Telescope 5.00 

267.  Clamp  and  Tangent  to  Telescope  axis 5.00 

268.  Offset-Standard  with  Counterpoise,  to  bring  the  Tel- 

escope over  the  line  of  zeros 7.50  $0.50 


Smaller  Field-Instruments. 


POCKET  SOLAR  COMPASS. 

POCKET  RAILROAD  COMPASS. 

POCKET  VERNIER  COMPASS. 

POCKET  PLAIN  COMPASS. 

GEOLOGISTS’  COMPASS. 
CLINOMETER  COMPASS. 

MINERS*  DIP-NEEDLE  COMPASS. 
DIAL  COMPASS. 


POCKET-COMPASSES 


"1 1 fE  MANUFACTURE  a variety  of  small  instruments 
v * so  portable  and  yet  so  efficient  that  they  are  often 
used,  in  preference  to  the  larger  ones,  for  preliminary  or 
reconnoissance  work. 


THE  POCKET  SOLAR  COMPASS. 


NO.  276o 

Price  as  shown,  with  tripod,  $105,00. 

132 


POCKET  SOLAR  COMPASS. 


133 


| ■ j . t v» 

The  Pocket  Solar  Compass  has  a needle  three  inches  long 
and  a limb  four  and  one-half  inches  in  diameter,  graduated 
to  half  degrees,  figured  one  row  0 to  180  each  way,  and 
reading,  by  its  one  double  vernier,  to  single  minutes. 

The  arrangement  of  the  plates  is  similar  to  that  of  the 
large  Solar  Compass,  the  lower  plate  carrying  the  sights 
plates  and  revolving  around  the  upper  or  compass- 
sights.  plate,  to  which  are  attached  the  solar  appa- 
ratus, levels,  etc.  There  is  a clamp  and  tangent  movement 
to  the  horizontal  limb  and  another  to  the  whole  instrument 
about  its  spindle,  both  now  made  with  an  opposing  spring. 

The  distance  between  the  sights  is  nearly  seven  inches  ; 
the  sights  themselves  are  about  four  and  one-half  inches 
high  and  have  a slit  and  hair  in  half  their  height  ; they  are 
hinged  so  as  to  fold  down  in  packing. 

The  compass-circle  is  arranged  with  a pinion  and  is 
movable,  so  as  to  set  off  the  variation  of  the  needle  to  five 
minutes  ; the  needle  has  a lifting  lever  by  which  it  is  raised 
against  the  glass. 

The  solar  apparatus  is  attached  to  the  upper  plate,  and 
consists  of  the  usual  hour , latitude  and  decimation  arcs, 

marked  respectively  A,  C and  B in  the 

SOLAR  PARTS.  . , • u ' _ ^ . . 

cut,  and  with  an  arm,  F F,  to  the  last 

named,  carrying  the  solar  lenses  and  lines. 

The  latitude  arc  is  graduated  to  half 

LATITUDE  ARC.  , , , , • ^ 

degrees,  and  reads  by  its  vernier  to  five 

minutes. 

declination  declination  arc  is  graduated  to 

arc.  quarter  degrees,  and  reads  by  its  vernier  to 
single  minutes. 

The  hour  arc  is  graduated  on  its  inner  edge  into  hours 
and  twelfths,  or  spaces  of  five  minutes  of  time,  the  index  on 
the  declination  arc  above  easily  enabling  one  to  read  single 


134 


POCKET  SOLAR  COMPASS. 


minutes  of  time.  The  hour-arc  is  made  movable  upon  its 
supporting  segment  to  either  side,  its  outer  edge  being  also 

divided  on  the  middle  portion  to  spaces  of 

HOUR-ARC.  £ - • , au 

five  minutes  of  time,  and  read  by  a vernier 

upon  the  segment  to  single  minutes.  In  this  way  the  equa- 
tion of  time  for  any  given  day  is  set  off  at  once,  and  the 
time  given  by  the  index  of  the  hour-arc  thus  made  to  agree 
with  mean  time,  or  that  given  by  the  ordinary  clock. 

The  solar  lenses  and  lines  are  placed  as  in  the  larger 
instruments,  the  declination  arc  being  also 
reversible  as  the  sun  changes  from  north 
to  south  of  the  equator. 

When  packed  in  the  case,  the  declination  arc  with  its 
arm  is  detached  from  the  hour-arc,  and  this  itself,  together 
with  the  latitude  arc,  folds  close  to  the  compass-box. 

The  Pocket  Solar  Compass  is  used  either  upon  a ball- 
spindle  with  staff  mountings,  or  as  shown,  upon  a light 
tripod  like  the  other  Pocket-Compasses,  and  often  with 
small  leveling-head  with  clamp  and  tangent  screws. 

Sometimes  a side  telescope  with  counterpoise  is  used  in 
addition  to  the  sight-vanes. 

The  adjustments  and  use  of  the  Pocket  Solar  Compass 
are  substantially  the  same  as  those  of  the  large  Solar  Com- 
pass already  described,  and  its  indications 
' are’so  accurate  that  it  will  give  the  true 
meridian  within  an  error  of  one  minute,  which,  taken  in  con- 
nection with  the  deflection  of  the  magnetic  needle,  will 
indicate  with  certainty  the  presence  and  direction  of  veins 
of  magnetic  iron  ore. 

We  have  the  assurance  of  competent  surveyors  that, 
while  it  is  much  more  portable,  it  is  also  very  nearly  as 
accurate  as  the  large  Solar  Compass.  Its  weight,  without 
box  or  tripod,  is  four  and  three-quarter  pounds. 


POCKET  RAILROAD  COMPASS. 


135 


NO.  285. 

Price  as  shown,  with  tripod,  $45.00. 


POCKET  RAILROAD  COMPASS. 

The  instrument  shown  is  a single  vernier  Railroad  Com- 
pass in  miniature.  The  limb  is  five  inches  in  diameter, 
graduated  to  half  degrees,  figured  one  row  0 to  180  each 
way,  and  reads  by  vernier  to  single  minutes.  The  needle 
is  three  and  one-half  inches  long,  and  its  variation  can  be 
set  off  to  single  minutes. 


136 


POCKET  RAILROAD  COMPASS. 


This  instrument  has  the  improved  spring  tangent,  and 
;the  vernier  placed  at  an  angle  of  thirty  degrees  with  the 
sights.  The  sights  are  made  to  fold  down  closely  for  con- 
venience in  packing,  and  are  each  made  half  slit  and  half 
hair,  so  that  fore  and  back-sights  may  be  taken  without 
turning  the  instrument. 

The  Pocket  Railroad  Compass  can  be  used  for  a great 
variety  of  work  and,  with  light  extension  tripod,  is  especially 
adapted  for  surveys  of  mines,  where  angles  must  be  taken 
independently  of  the  needle. 

The  price,  with  staff  mountings,  is  $40,  with  light  tripod 
$45,  and  with  extension  tripod  $50. 

POCKET  RAILROAD  COMPASS  WITH  TELESCOPE. 

In  the  cut  on  page  137  we  show  a form  of  the  Pocket 
Railroad  Compass  which  is  adapted  to  receive  the  Tele- 
scopic Sight. 

The  plates  are  circular  and  the  sights  are  made  half 
slit  and  half  hair,  and  are  jointed  so  as  to  fold  down  close 
to  the  glass.  The  needle  is  four  and  one-half  inches  long, 
and  there  is  an  arc  with  vernier,  on  the  outside  of  the  com- 
pass-plate, for  setting  off  the  variation  of  the  needle. 

The  instrument  has  a limb  about  four  inches  in  diam- 
eter, placed  inside  the  compass-circle,  and  reading  to  single 
minutes  by  a vernier.  A clamp  and  tangent  movement  is 
added  to  the  spindle. 

The  sights  being  inclined  to  each  other,  as  shown,  a 
short  standard  supporting  the  telescope  is  secured  by  two 
milled  head  screws  to  the  tops  of  the  sights,  and  thus  a 
telescope  is  placed  in  position,  making  the  instrument  in 
effect  a very  light  Surveyor’s  Transit. 

The  attachments  of  vertical  circle,  level  and  clamp  and 
tangent,  as  shown  in  the  figure,  may  also  be  added,  and 


POCKET  R.  R.  COMPASS  WITH  TELESCOPE.  13 


NO.  293. 

Price,  as  shown,  $83.00. 


138  POCKET  R.  R.  COMPASS  WITH  TELESCOPE, 


thus  the  means  furnished  for  taking  grades  and  running 
levels  with  accuracy  sufficient  for  the  common  practice  of 
the  surveyor. 

The  sights  are  placed  to  one  side  of  the  line  of  zeros, 
and  the  telescope  is  thus  brought  into  that  line  and  over 
the  center  of  the  instrument. 

The  short  standard  can  be  detached  with  the  telescope 
and  placed  in  the  case,  or  replaced,  in  a few  moments’  time 
without  deranging  any  of  the  adjustments. 

The  Pocket  Railroad  Compass  can  be  used  either  on  a 
staff  or  with  small  tripod,  and,  if  desired,  with  small 
leveling-head,  as  shown. 

Weight  of  the  Pocket  Railroad  Compasses,  includ- 
ing the  brass  mountings  of  the  staff,  but  without  tripod  : 

No.  285,  3J-inch  Compass,  about 4 lbs. 

No.  288,  4J-inch  Compass,  about 4J  “ 

Nos.  290,  291  and  292,  4J-inch  Compass,  about 6^  “ 

No.  293,  4J-inch  Compass,  about 7f  “ 

PRICES. 

No.  Price. 

285.  Pocket  Railroad  Compass,  one  vernier  to  limb,  limb  5 
inches  diameter,  reading  to  1 minute,  and  with  clamp 
and  tangent,  3J-inch  needle,  folding  sights,  two  levels 

and  staff  mountings  ; see  page  133 $40.00 

288.  Pocket  Railroad  Compass,  one  vernier  to  limb  inside  the 
compass-circle  and  reading  to  one  minute,  with  clamp 
and  tangent,  4J-inch  needle,  folding  sights,  two  levels 

and  staff  mountings 33.00 

290.  Pocket  Railroad  Compass,  4J-inch  needle,  clamp  and 
tangent  to  lirfib,  limb  reading  to  1 minute,  clamp  and 
tangent  to  main-  spindle  or  socket,  and  fitted  with  our 
Telescopic  Sight  No.  260,  with  the  extras  of  level,  ver- 
tical circle  to  5 minutes,  and  clamp  and  tangent  to 


telescope  axis.  Price,  including  tripod 73.00 

291.  Same  as  above,  but  with  Telescopic  Sight  No.  261 75.00 

292.  “ “ “ “ “ “ “ No.  262 78.00 

293.  “ “ “ “ “ “ “ No.  262,  and 

with  leveling-adopter,  as  shown  on  page  135 83.00 


POCKET  VERNIER  COMPASS. 


139 


No.  300  — Price  as 
shown,  3/^-inch  needle, 
with  tripod,  $21.00. 


No.  305  — With  434- 
inch  needle,  and  tripod, 
$23.00. 


POCKET  VERNIER  COMPASS. 


The  Pocket  Vernier  Compass  is  an  excellent  and  port- 
able instrument  for  preliminary  work,  having  a fine  needle 
and  a vernier  and  clamping  nut,' by  which  the  sights  can  be 
placed  at  an  angle  with  the  line  of  zeros,  so  as' to  set  off  the 
variation  of  the  needle  as  with  the  Vernier  Compass. 

The  instrument  has  folding  sights,  two  levels  and  staff 
mountings,  and  is  packed  in  a mahogany  case. 

The  sights  in  the  three  and  one-half  inch  Compass  are 
made,  as  shown  in  the  cut,  with  a slit  in  the  south  vane  and 
a hair  in  the  north  vane  for  readily  finding  the  object  ; but 
in  the  four  and  one-half  inch  Compass  the  sights  are  made 
with  half  slit  and  half  hair,  as  shown  on  page  135. 


140 


POCKET  VERNIER  COMPASS. 


They  also  fold  down  to  the  Compass  when  it  is  packed  in 
the  case.  The  Compass  is  furnished  with  staff  mountings, 
and  is  often  used  with  a light  tripod. 

When  desired  to  set  off  the  variation  more  readily,  a rack 
movement  with  pinion  is  supplied  at  an  extra  cost  of  $4.00. 

We  make  two  sizes  of  the  Pocket  Vernier  Compass, 
having  needles  respectively  three  and  one-half  and  four 

and  one-half  inches  long  ; both  have 
the  compass-circle  graduated  to  half 
degrees..  In  the  smaller  size  the  variation  vernier  reads 
to  five  minutes  ; in  the  larger  size  the  variation  may  be 
set  off  to  single  minutes. 

Compass  with  3J-inch  needle  weighs  about  If  lbs. 


SIZE  AND  WEIGHT. 


4* 


2f 


POCKET  VERNIER  COMPASS  WITH  TELESCOPE. 

The  arrangement  for  attaching  a telescope  and  extras 
to  the  sights  of  the  four  and  one-half-inch  Pocket  Vernier 
Compass  is  shown  on  page  141,  making  this  little  instru- 
ment a Transit-Compass  for  ordinary  land-surveying  and 
reconnoissance,  with  power  to  give  levels  and  grades  with 
accuracy  sufficient  for  ordinary  practice.  The  sights  in  such 
an  arrangement  are  placed  at  one  side,  that  the  telescope 
may  be  directly  over  the  center,  and  the  instrument  should 
have  a clamp  and  tangent  movement  for  the  spindle,  as 
shown  in  the  figure.  When  packed  for  transportation,  the 
telescope  and  support  are  detached  from  the  sights  and 
packed  separately  in  the  case.  Staff  mountings  are  always 
furnished  with  these  Compasses ; and  a light  tripod,  as 
shown,  is  very'  generally  added. 

The  weight  of  Compass  No.  312  without 
tripod  is  about  four  and  one-half  pounds  ; the 
tripod  weighs  about  four  pounds. 


POCKET  VERNIER  COMPASS  WITH  TELESCOPE.  141 


NO.  312. 

Price,  complete  as  shown,  $63.00. 


No.  PRICES. 

310.  Pocket  Vernier  Compass,  4%-inch  needle,  with  clamp  and  tangent  to  the 
main  spindle  or  socket,  and  fitted  with  our  new  Telescopic  Sight  No.  260, 
with  the  extras  of  level,  vertical  circle  to  5',  and  clamp  and  tangent  to 


telescope  axis.  Price,  including  tripod $58.00 

311.  Same  as  above,  but  with  Telescopic  Sight,  No.  261 60.00 

312.  “ “ “ “ “ No.  262,  as  shown 63.00 


142  POCKET  PLAIN  COMPASSES. 

POCKET  PLAIN  COMPASSES. 

Besides  the  Pocket  Vernier 
Compass,  we  also  furnish  a 
similar  instrument  without  a 
vernier,  which  is  often  found 
very  serviceable.  The  Pocket 
Plain  Compasses  are  made  with 
two  and  one-half  and  three 
and  one-half-inch  needles,  and 
supplied  with  levels  and  staff 
Nos.  316  and  318.  mountings  or  not,  as  may  be 
desired.  They  are  packed  in  a light  mahogany  case,  the 
sights  folding  down  close  to  the  glass. 

PRICES. 

No.  Price.  Post. 

315.  Pocket  Plain  Compass,  2J-inch  needle,  with  fold- 

ing sights $ 8.00  $0.25 

316.  Pocket  Plain  Compass,  2J-inch  needle,  with  fold- 

ing sights  and  staff  mountings., 10.00  .35 

317.  Pocket  Plain  Compass,  3J-inch  needle,  with  fold- 

ing sights 10.00  .40 

318.  Pocket  Plain  Compass,  3J-inch  needle,  with  fold- 

ing  sights  and  staff  mountings 12.00  .50 

319.  Pocket  Plain  Compass,  3J-inch  needle,  with  fold- 

ing sights,  two  levels  and  staff  mountings 13.50  .50 

A convenient  appliance  is  shown  in 
No.  327,  at  a , for  use  with  Pocket-Com- 
leveling-  passes  Nos.  275  to  319, 
adopter,  giving  in  connection  with 
the  ball  a rapid  and  accurate  means 
of  leveling  any  of  the  smaller  instru- 
ments. The  attachment  weighs  less 
than  one  pound,  and  can  be  used  on 
the  tripod  by  merely  removing  the 
brass  cap.  Its  value  and  use  are  ap- 
parent upon  inspection.  Price,  $5.00. 


NO.  327. 


GEOLOGISTS'  COMPASS. 


143 


GEOLOGISTS'  COMPASS. 


NO.  335. 

Price,  as  shown,  $24.00. 


We  show  here  a popular  instrument  for  topographical 
work,  known  as  the  Geologists’  Compass.  It  is  made 
of  aluminum  to  secure  light  weight,  and  has  a needle  two 
and  five-eighths  inches  long  enclosed  with  its  compass- 
circle  in  a circular  bo$  set  upon  a base  four  inches  square, 
the  edges  of  which  are  beveled  and  graduated,  two  of  them 
for  a tangent  scale  and  the  other  two  with  scales  of  eighths 
and  tenths  of  inches.  The  compass-circle  is  made  movable 
and,  by  a vernier  attached  to  it  on  the  inside,  the  varia- 
tion of  the  needle  can  be  set  off  to  five  minutes.  On  the 
south  side  of  the  compass-face  is  an  arc  of  one  hundred  and 


144 


CLINOMETER  COMPASS . 


eighty  degrees,  figured  on  each  side  of  the  zero  line  from  0 
to  90.  The  index  point,  a little  pendulum  hung  from  the 
center-pin,  indicates  on  this  arc  the  angle  of  slope  when 
the  Compass  is  placed  so  that  it  rests  on  its  south  edge. 
On  the  outside  of  the  circular  box  containing  the  compass- 
circle  is  a movable  circle,  beveled  and  graduated  on  its  upper 
edge  and  figured  from  0 to  90,  and  having  at  each  quadrant 
a slit  cut  for  sighting.  Two  folding  sights  are  attached  to 
the  edge  of  the  circular  box.  The  Compass  is  supported 
on  a simple  ball-spindle  and  socket  with  staff  mountings, 
and  is  packed  in  a mahogany  box. 


CLINOMETER  COMPASS. 


NO.  338. 

Price,  as  shown,  $16.  (See  page  145.) 


CLINOMETER  COMPASS. 


145 


CLINOMETER  COMPASS. 

Another  form  of  Pocket-Compass  is  shown  on  page  144. 
It  is  made  of  brass,  and  is  known  as  the  Clinometer  Com- 
pass. It  has  a needle  three  and  one-half  inches  long, 
enclosed  with  its  compass-circle  in  a circular  box  set  upon 
a base  four  and  one-half  inches  square.  On  one  edge  of 
this  base  is  placed  the  rectangular  side  upon  which  the 
Compass  may  be  set  in  determining  grades. 

The  small  pendulum  swinging  from  the  center-pin  des- 
ignates, by  its  index,  the  degree  of  slope  upon  the  gradu- 
ated arc  on  the  compass-face.  Two  folding  sights  are 
attached  to  the  circular  box,  and  two  small  levels  are  placed 
at  right  angles  with  each  other  upon  the  base.  The  Com- 
pass is  supported  upon  a simple  ball-spindle  and  socket, 
with  staff  mountings,  and  is  packed  in  a mahogany  box. 


146 


MINERS'  DIP- COMPASS. 


MINERS'  OR  DIP-COMPASS. 

The  Dip-Compasses,  two  forms  of  which  are  shown  on 
this  page,  consist  essentially  of  a magnetic  needle  so  sus- 
pended as  to  move  readily  in  a vertical  direction,  the  angle 
of  inclination,  or  “dip,”  being  measured  upon  the  grad- 
uated rim  of  the  compass-circle. 

When  in  use,  the  ring  or  bail  is  held  by  the  hand,  and 
the  compass-box  by  its  own  weight  takes  a vertical  position. 
It  must  also  be  held  in  the  plane  of  the  magnetic  meridian. 


NOS.  340  AND  341.  NOS.  344  AND  345. 

Price,  $12.00.  Price,  $12.00  and  $15.00. 


MINERS'  DIP-COMPASS. 


147 


In  this  position,  the  needle,  when  unaffected  by  the  at- 
traction of  iron,  assumes  a horizontal  line,  as  shown  by  the 
zeros  of  the  circle.  When  brought  over  any  mass  of  mag- 
netic iron  ore  it  dips,  and  thus  detects  the  presence  of  such 
ore  with  certainty. 

If  the  Miners’  Compass,  No.  340  or  341,  is  held  horizon- 
tal it  serves  as  an  ordinary  Pocket-Compass,  and  thus  indi- 
cates the  magnetic  meridian,  in  the  plane  of  which  it  should 
be  held  when  used  to  ascertain  the  dip. 

Several  different  styles  of  this  instrument  are  made. 
Those  shown  as  Nos.  340  and  341;  with  a three-inch  needle, 
have  the  two  sides  of  glass,  and  are  provided  with  a stop 
for  the  needle  which  is  worked  by  the  little  brass  knob 
between  the  ends  of  the  ring. 

The  Norwegian  Compass,  Nos.  344  and  345,  is  a 
modification  of  an  instrument  used  in  northern  Europe. 

It  has  a needle  either  three  or  four  inches  long,  resting 
upon  a single  vertical  pivot  so  as  to  move  freely  in  a hori- 
zontal direction.  At  the  same  time,  being  attached  to  the 
needle-cap  by  two  delicate  pivots,  one  on  each  side,  it  is 
free  to  dip  like  the  needle  of  the  ordinary  Miners’  Compass. 


PRICES. 

No.  Price.  Post. 

340.  Miners’  Compass,  3-inch  needle,  glass  on  both  sides, 

wood  box,  stop  to  needle $12.00  $0.25 

341.  Miners’  Compass,  3-inch  needle,  glass  on  both  sides, 

brass  covers,  stop  to  needle 12.00  .35 

344.  Norwegian  Compass,  3-inch  needle,  glass  on  both 

sides,  brass  covers 12.00  .35 

345.  Same  as  No.  344,  but  with  4-inch  needle 15.00  .50 


Note. — No  instrument  made  that  will  indicate  the  presence  of  gold  or  silver. 


148 


DIAL  COMPASS. 


BRASS  DIAL  COMPASS. 


NO.  348. 

Price,  $18.00. 


This  little  instrument  has  a needle  two  and  five-eighths 
inches  long,  and  with  its  compass-circle  is  enclosed  in  a 
circular  box  set  upon  a base  four  inches  square,  three 
edges  of  which  are  chamfered  and  graduated,  the  one  on 
the  W-side  of  the  Compass  into  inches  and  tenths  and  the 
two  others  into  degrees  and  half  degrees,  and  figured  from 
a center  on  the  south-west  corner  of  the  base. 

The  compass-circle  is  movable,  in  order  to  set  off  the 
variation  of  the  needle,  and  has  a vernier  attached  to  it 
on  the  inside,  reading  a graduated  arc  on  the  face  of  the 
Compass  to  five  minutes. 


DIAL  COMPASS. 


149. 


There  is  also  on  the  south  side  of  the  face  an  arc  of 
one  hundred  and  eighty  degrees,  figured  from  0 to  90  on 
each  side  of  the  south  or  zero-line  of  the  face. 

A pendulum  with  index-point  hung  from  the  center-pin 
reads  this  arc  when  the  compass  is  set  up  vertical  on  the 
raised  south  edge,  thus  making  it  a clinometer  or  slope- 
measurer. 

The  sight  is  hinged  so  as  to  fold  in  packing,  but  when 
erect  makes  taut  a fine  silk  thread,  attached  at  one  end  to 
the  sight  and  at  the  other  to  an  hour-circle  above  the 
compass-glass,  at  an  angle  with  the  plane  of  the  hour-circle 
equal  to  th,at  of  the  latitude  of  the  place  where  the  Com- 
pass is  used.  The  hour-circle  is  divided  for  any  required 
latitude,  as  a sun-dial,  the  threads  serving  as  a gnomon  to 
give  apparent  time  with  the  sun. 

The  Dial  Compass  is  extensively  used  in  this  country  in 
regions  where  there  is  local  attraction,  and  it  is  desirable  to 
have  a simple  means  of  determining  the  meridian  inde- 
pendently of  the  needle. 

This  can  be  easily  and  quickly  done  by  turning  the 
Compass,  with  dial  graduated  for  the  latitude  of  the  place, 
until  the  shadow  of  the  thread  when  the  Compass  is  held 
level  indicates  local  time  on  the  dial.  The  line  of  zeros 
will  then  be  in  the  meridian. 

The  needle  may  then  be  set  to  the  meridian  by  laying 
off  the  variation,  and  any  deflection  of  the  needle  from  the 
true  meridian  will  indicate  the  presence  of  veins  of 
magnetic  iron  ore. 

Extra  hour-circles,  graduated  for  any  latitude  and  to  fit 
the  same  Compass,  can  be  furnished  at  an  extra  cost  of 
$5.00  each. 

Staff  mountings,  including  ball-spindle  and  socket,  can 
also  be  furnished  at  an  extra  cost  of  $2.50. 


150 


DIAL  COMPASS.  . 


ALUMINUM  DIAL  COMPASS. 


The  illustration  shows  an  improved  form  of  the  Dial 
Compass,  made  of  aluminum,  and  differing  from  our  usual 
pattern  in  several  respects.  This  new  instrument  is  of  the 
same  size  and  has  the  same  parts  as  the  Dial  Compass, 
shown  on  page  148,  and  in  addition  has  a movable  circle 
graduated  on  its  beveled  edge  from  zero  to  ninety  degrees. 
At  each  quadrant  there  is  a slit  cut  for  sighting,  and  an 
open  sight  is  furnished  with  the  Compass,  to  be  placed 
upon  the  clinometer  base  when  desired,  and  used  in  con- 
junction with  the  regular  sight.  The  instrument  is  mounted 
upon  a small  ball-spindle  and  socket  with  staff  mountings, 
and  is  packed  in  a mahogany  box. 


LEVELING-INSTRUMENTS. 


ENGINEERS’  Y-LEVELS. 

ARCHITECTS’  Y-LEYELS. 


DRAINAGE  LEVELS. 


ENGINEERS’  Y-LEVELS. 


F THE  different  varieties  of  Leveling-Instruments, 


the  Y-Level  is  universally  preferred  by  American 
Engineers  on  account  of  its  easy  adjustment  and  superior 
accuracy. 

Of  these  levels  we  manufacture  five  different  sizes, 
having  telescopes  twenty-two,  twenty,  eighteen,  fifteen,  and 
twelve  inches  in  length.  The  cut  on  page  153  represents 
our,  twenty-inch  Y-Level. 

The  Telescope  has  near  its  end  two  rings  of  bell- 
metal,  turned  very  truly  and  of  exactly  the  same  diameter. 


are  brought  down  upon  the  rings,  by  pushing  in  the  taper- 
ing pins. 

The  Telescope  has  a rack  and  pinion  movement  to 
both  object-glass  and  eyepiece,  and  an  adjustment  for 
centering  the  eyepiece,  shown  at  A A in  the  sectional  view 
of  the  instrument,  page  154,  and  another,  seen  at  C,  for 
insuring  the  accurate  projection  of  the  object-glass  slide. 

Both  of  these  are  completely  concealed  from  observa- 
tion and  disturbance  by  thin  bands  which  screw  over  them. 

The  Telescope  has  also  a shade  over  the  object-glass,  so 
made  that,  while  it  may  be  readily  moved  on  its  slide  over 
the  glass,  it  cannot  be  dropped  off  and  lost. 

A small  Compass,  without  sights  and  with  three-inch 


TELESCOPE. 


On  these  rings  it  rotates  in  the  Ys,  or  it 
can  be  clamped,  when  the  clips  of  the  Ys 


COMPASS. 


needle,  is  sometimes  attached  to  the  telescope 
and  used  to  obtain  the  bearing  of  lines ; its 


extra  cost  is  $10.00. 


152 


ENGINEERS'  LEVELS. 


153 


NO.  376. 

20-INCH  Y-LEVEL. 

Price  as  shown,  including  Tripod,  $110.00. 


154 


ENGINEERS'  LEVELS. 


ENGINEERS'  LEVELS. 


155 


A Horizontal  Circle,  three  and  one-half  inches  in  diam- 
eter, can  be  fitted  to  the  leveling-head  of  the  Y-Level. 
horizontal  The  circ^e  ls  graduated  to  whole  degrees, 

circle.  and  is  read  by  vernier  to  five  minutes. 

The  extra  cost  for  this  attachment  is  $15.00. 

The  interior  construction  of  the  telescope  will  be  read- 
object-glass  ^7  understood  from  the  sectional  cut,  page 
slide.  154,  which  exhibits  the  adjustment  that 
insures  the  accurate  projection  of  the  object-glass  slide. 

• This  is  peculiar  to  our  instruments,  and  is  always  made 
so  permanently  as  to  need  no  further  attention  at  the  hands 
of  the  engineer. 

The  necessity  for  such  an  adjustment  will  appear  when 
we  state  that  it  is  almost  impossible  to  make  a telescope 
tube  a perfectly  straight  cylinder  on  its  inner  surface. 

Such  being  the  case,  it  is  evident  that  the  object-glass 
slide  which  is  fitted  to  this  surface,  and  moves  in  it,  must 
partake  of  its  irregularity,  ^o  that  the  glass  and  the  line  of 
collimation  depending  upon  it,  though  adjusted  in  one  posi- 
tion of  the  slide,  will  be  thrown  out  when  the  slide  is  moved 
out  or  in. 

To  prove  this,  let  any  Level  be  selected,  which  is  con- 
structed in  the  usual  manner,  and  the  line  of  collimation 
adjustment  upon  an  object  taken  as  near  as  the  range  of 
the  slide  will  allow  ; then  let  another  be  selected  as  distant 
as  may  be  clearly  seen  ; upon  this  rotate  the  wires  and 
they  will  generally  be  found  out  of  adjustment,  sometimes 
to  a degree  fatal  to  any  confidence  in  the  accuracy  of  the 
instrument.  The  arrangement  adopted  by  us  to  correct 
this  imperfection,  and  which  perfectly  accomplishes  its 
purpose,  is  shown  in  the  sectional  cut. 

Here  are  seen  the  two  bearings  of  the  object-glass 
slide,  one  being  in  the  narrow  metal  ring  slightly 


156 


ENGINEERS'  LEVELS. 


less  than  the  diameter  of  the  main  tube,  the  other  in  the 
small  adjustable  ring,  also  of  metal,  shown  at  C,  and  sus- 
pended by  four  screws  in  the  middle  of  the  telescope. 

Advantage  is  here  taken  of  the  fact  that  the  rays  of 
light  are  converged  by  the  object-glass,  so  that  none  are 
obstructed  by  the  contraction  of  the  slide  except  those 
which  diverge  and  which  ought  always  to  be  intercepted 
and  absorbed  in  the  blackened  surface  of  the  interior  of 
the  slide. 

Now,  in  such  a telescope,  the  perfection  of  movement 
of  the  slide  depends  entirely  upon  its  exterior  surfaces  at 
the  points  of  the  two  bearings.  These  surfaces  are  accu- 
rately turned,  concentric  and  parallel  with  each  other,  and, 
being  fitted  to  the  rings,  it  is  only  necessary  to  adjust  the 
position  of  the  smaller  ring  so  that  its  center  will  coincide 
with  that  of  the  optical  axis  of  the  object-glass.  When  this  has 
been  done  no  further'correction  will  be  necessary  unless  the 
telescope  should  be  seriously  injured.  The  manner  in  which 
the  adjustment  of  the  object-glass  slide  is  effected  will  be 
considered  when  we  come  to  speak  of  the  other  adjustments. 

rack  and  As  seen 'm  cut,  the  telescopes  of  our 
pinion.  eighteen,  twenty,  and  twenty-two  inch 
Levels  are  furnished  with  rack  and  pinion  movement  to 
both  object-glass  and  eyepiece. 

The  advantages  of  an  eyepiece  pinion  are  that  the  eye- 
piece can  be  shifted  without  danger  of  disturbing  the  tele- 
scope, and  that  the  wires  are  more  certainly  brought  into 
distinct  view,  so  as  to  avoid  any  error  of  observation  arising 
from  the  instrumental  parallax. 

The  level-tube,  with  ground  vial  and  scale,  is  attached  to 
the  under  side  of  the  telescope,  and  fur- 
level  vial.  at  different  ^nds  with  the  usual 

movements  in  both  horizontal  and  vertical  directions. 


ENGINEERS'  LEVELS. 


157 


The  aperture  of  the  tube,  through  which  the  glass  vial 
is  seen,  is  about  five  and  one-quarter  inches  long,  and  is 
crossed  at  the  middle  by  a rib  or  bridge  which  greatly 
strengthens  the  tube. 

The  level-vial  is  made  of  glass  tube,  selected  so  as  to 
have  an  even  bore  from  end  to  end,  and  finely  ground  on 
its  interior  surface,  so  that  the  run  of  the  air-bubble  may 
be  uniform  throughout  its  whole  range.  The  level-scale 
which  extends  over  the  whole  length  is  graduated  to 
tenths  of  an  inch  and  figured  at  every  fifth  division,  count- 
ing from  zero  at  the  middle  of  the  bridge.  The  scale  is 
set  close  to  the  glass. 

The  sensitiveness  of  a ground  level  is  best  determined 
by  an  instrument  called  a level-tester,  consisting  of  a bar 
with  two  Ys  to  hold  the  level-tube,  and  pivoted  at  one 
end,  while  at  the  other  end  is  a micrometer  wheel  attached 
to  the  top  of  a fine-threaded  screw  which  raises  the  end  of 
the  tester  very  gradually.  The  number  of  divisions  passed 
over  on  the  perimeter  of  the  wheel,  in  carrying  the 
bubble  over  a tenth  of  an  inch  on  the  scale,  is  the 
index  of  the  delicacy  of  the  level.  In  the  tester  which 
we  use,  a movement  of  ten  divisions  of  the  wheel 
to  one  of  the  scale  indicates  the  degree  of  delicacy 
generally  preferred  for  railroad  engineering.  For  canal 
work  a more  sensitive  bubble  is  often  required,  as,  for 
instance,  one  of  five  to  seven  divisions  of  the  wheel  to  one 
of  the  scale. 

The  Ys  of  our  levels  are  made  large  and  strong,  of 
the  best  bell-metal,  and  each  have  two  nuts  adjustable  with 
the  ordinary  steel  pin.  The  clips  are  brought 

YS 

down  on  the  rings  of  the  telescope  tube  by  the 
Y-pins,  which  are  made  tapering,  so  as  to  clamp  the  rings 
firmly.  The  clip  of  one  of  the  Ys  has  a little  pin  pro- 


158 


ENGINEERS'  LEVELS. 


LEVEL-BAR, 


SOCKET. 


jecting  from  it,  which,  entering  a recess  in  the  edge  of  the 
ring,  insures  the  horizontal  position  of  the  cross-wire. 

The  level-bar  is  made  round,  of  the  best  bell-metal,  and 
shaped  for  greatest  strength  in  the  parts* 
most  liable  to  sudden  strains.  Connected 
with  the  level-bar  is  the  head  of  the  leveling-socket. 

The  socket  is  compound  ; tTie  inner  spindle,  D (see  page 
154),  upon  which  the  whole  instrument  is  supported,  is  made 
of  steel  and  nicely  ground  so  as  to  turn 
evenly  and  firmly  in  a hollow  cylinder  of 
bell-metal  ; this  again  has  its  exterior  surface  fitted  and 
ground  to  the  main  socket,  E E,  of  the  leveling-head. 

The  bronze  cylinder  is  held  upon  the  spindle  by  a 
washer  and  screw,  the  head  of  the  latter  having  a hole 
5 in  its  center  through  which  the  string  of  the  plummet 
is  passed. 

The  upper  part  of  the  instrument,  with  the  socket,  may 
be  detached  from  the  leveling-head  ; and  this  also,  as  is  the 
case  with  all  our  instruments,  can  be  unscrewed  from  the 
tripod  head  ; but  all  the  Y-Levels  made  by  us  are  packed 
in  the  case  complete  with  leveling-head,  experience  having 
shown  that  there  is  thus  less  danger  of  injury  in  transporta- 
tion. It  will  be  seen  from  the  cut  that  the  arrangement  just 
described  allows  long  sockets  and  yet  brings  the  whole  in- 
strument down  as  closely  as  possible  to  the  leveling-head, 
both  objects  of  great  importance  in  the  construction  of  any 
instrument. 

The  leveling-head  has  the  same  plates  and  leveling- 

leveling-  screws  as  described  in  the  account  of  the 
head.  Engineers'  Transit.  The  tangent  screw 
has  also  an  opposing  spring  as  there  described. 

For  the  fifteen-inch  level  we  make  a leveling-head 
similar  to  that  used  with  the  lighter  Engineers’  Transit, 


ENGINEERS'  LEVELS. 


159 


THE  ADJUSTMENTS . 

The  adjustment  of  the  object-glass  slide  is  peculiar  to 
our  instruments,  and  is  always  made  by  us  so  permanently 
as  to  need  no  further  attention  at  the  hands  of  the  en- 
gineer, unless  in  case  of  derangement  by  accident. 

To  adjust  the  object-glass  slide,  the  maker  selects  an 
object  as  distant  as  may  be  distinctly  observed,  and  upon 
object-glass  ^ adjusts  the  line  of  collimation,  in  the 
slide.  manner  described  on  page  161,  making  the 
center  of  the  wires  to  rotate  without  passing  either  above 
or  below  the  point  or  line  assumed. 

In  this  position,  the  slide  will  be  drawn  in  nearly  as  far 
as  the  telescope  tube  will  allow. 

With  the  pinion-head  he  then  moves  out  the  slide  until 
an  object,  distant  about  ten  or  fifteen  feet,  is  brought 
clearly  into  view  ; again  rotating  the  telescope  in  the  Ys 
he  observes  whether  the  wires  will  reverse  upon  this  second 
object. 

Should  this  happen  to  be  the  case,  he  will  assume  that 
as  the  line  of  collimation  is  in  adjustment  for  these  two  dis- 
tances, it  will  be  so  for  all  intermediate  ones,  since  the 
bearings  of  the  slide  are  supposed  to  be  true  and  their 
surfaces  parallel  with  each  other. 

If,  however,  as  is  most  probable,  either  or  both  wires 
fail  to  reverse  upon  the  second  point,  he  must  then,  by  esti- 
mation, remove  half  the  error  by  the  screws  at  C (page 
154),  at  right  angles  with  the  wire  sought  to  be  corrected, 
remembering  at  the  same  time  that,  on  account  of  the  in- 
verting power  of  the  eyepiece,  he  must  move  the  slide  in 
the  direction  which  apparently  increases  the  error.  When 
both  wires  in  succession  have  been  thus  treated,  the  line  of 
coiiimation  is  adjusted  on  the  near  object,  and  the  tele- 


160 


ENGINEERS'  LEVELS. 


scope  again  brought  upon  the  most  distant  point  ; here  the 
tube  is  again  rotated,  the  reversion  of  the  wires  upon  the 
object  once  more  tested,  and  the  correction,  if  necessary, 
made  in  the  same  manner. 

He  proceeds  thus  until  the  wires  will  reverse  upon  both 
objects  in  succession  ; the  line  of  collimation  will  then  be 
in  adjustment  at  these  and  all  intermediate  points,  and  by. 
bringing  the  screw-heads,  in  the  course  of  the  operation,  to 
a firm  bearing  upon  the  washers  beneath  them,  the  adjusta- 
ble ring  will  be  fastened  so  as  to  need  no  further  adjust- 
ment for  many  years. 

When  this  has  been  completed  the  thin  brass  ferule  is 
screwed  over  the  outside  ring,  concealing  the  screw-heads 
and  avoiding  the  danger  of  their  disturbance  by  an  inex- 
perienced operator.  * 

In  making  this  adjustment,  it  is  always  best  to  bring 
the  wires  into  the  center  of  the  field  of  view  by  moving  the 
screws,  A A,  (page  154,)  working  in  the  centering-ring  of 
the  eyepiece  tube. 

Should  the  engineer  desire  to  make  the  adjustment 
of  the  object-glass  slide,  it  will  be  necessary  to  remove 
the  level-tube,  in  order  that  the  screw  immediately 
above  its  scale  may  be  operated  upon  with  the  screw- 
driver. 

The  adjustments  which  are  common  to  all  Y-Levels, 
and  with  which  the  engineer  should  be  familiar,  are  : 

1.  To  adjust  the  line  of  collimation,  or,  in  other  words, 
to  bring  the  cross-wires  into  the  longitudinal  axis,  so  that 
their  point  of  intersection  will  remain  on  any  given  point 
during  an  entire  rotation  of  the  telescope. 

2.  To  bring  the  level-bubble  parallel  with  the  bear- 
ings of  the  Y-rings  or  with  the  longitudinal  axis  of  the 
telescope. 


ENGINEERS'  LEVELS. 


161 


3.  To  adjust  the  Ys,  or  to  bring  the  bubble  into  a 
position  at  right  angles  with  the  vertical  axis  of  the  in- 
strument. 

To  adjust  the  line  of  collimation,  set  the  tripod  firmly, 
remove  the  Y-pins  from  the  clips  so  as  to  allow  the  tele- 
line  of  scope  to  turn  freely,  clamp  the  instrument 
. collimation.  to  the  leveling-head,  and  by  the  leveling 
and  tangent  screws  bring  either  of  the  wires  upon  the 
clearly  marked  edge  of  some  object,  distant  from  one  hun- 
dred to  five  hundred  feet.  Then  with  the  hand  carefully 
rotate  the  telescope  half-way  around,  so  that  the  position 
of  the  same  wire  is  compared  with  the  object  selected. 

Should  it  be  found  above  or  below,  bring  it  half-way 
back  by  the  capstan-  head  screws  at  right  angles  with  it, 
always  remembering  the  inverting  property  of  the  eye- 
piece ; now  bring  the  wire  again  upon  the  object  and  re- 
peat the  first  operation  until  it  will  reverse  correctly. 
Proceed  in  the  same  manner  with  the  other  wire  until  the 
adjustment  is  completed. 

Should  both  wires  be  much  out,  it  will  be  well  to  bring 
both  nearly  correct  before  either  is  entirely  adjusted. 

When  this  is  effected,  unscrew  the  covering  of  the  eye- 
piece centering-screws,  shown  in  the  sectional  view  at  A A, 
page  152,  and  move  each  pair  in  succession  with  a screw- 
driver until  the  wires  are  brought  into  the  center  of  the 
field  of  view.  The  inverting  property  of  the  eyepiece 
does  not  affect  this  operation,  and  the  screws  are  moved 
directly. 

To  test  the  correctness  of  the  centering,  rotate  the  tele- 
scope, and  observe  whether  it  appears  to  shift  the  position 
of  an  object.  Should  any  movement  be  perceived,  the  cen- 
tering is  not  perfectly  effected.  In  all  telescopes  the  line  of 
collimation  depends  upon  the  relation  of  the  cross-wires  and 


162 


ENGINEERS'  LEVELS. 


object-glass  ; and  therefore  the  movement  of  the  eyepiece 
does  not  affect  the  adjustment  of  the  wires  in  any  respect. 

When  the  centering  has  once  been  effected  it  remains 
permanent,  the  cover  being  screwed  on  again  to  conceal 
and  protect  it  from  derangement  at  the  hands  of  the 
curious  and  inexperienced  operator. 

To  adjust  the  level-bubble,  clamp  the 
LEVEL-VIAL.  r 

instrument  over  either  pair  of  leveling- 

screws,  and  bring  the  bubble  into  the  middle  of  the  tube. 

Now  turn  the  telescope  in  the  Ys,  so  as  to  bring  the 
level-tube  to  one  side  of  the  middle  of  the  bar.  Should 
the  bubble  run  to  the  end,  it  would  show  that  the  vertical 
plane  passing  through  the  middle  of  the  bubble  was  not 
parallel  to  that  drawn  through  the  axis  of  the  telescope 
rings. 

To  correct  the  error,  bring  the  bubble,  by  estimation, 
half-way  back  with  the  capstan-head  screws  on  each  side 
of  the  level-holder,  placed  usually  at  the  object-glass  end 
of  the  tube. 

Again  bring  the  level-tube  over  the  middle  of  the  bar 
and  the  bubble  to  the  middle,  turn  the  level  to  either  side, 
and,  if  necessary,  repeat  the  correction  until  the  bubble 
will  keep  its  position  when  the  tube  is  turned  half  an  inch 
or  more  to  either  side  of  the  middle  of  the  bar. 

The  necessity  for  this  operation  arises  from  the  fact  that, 
when  the  telescope  is  reversed  end  for  end  in  the  Ys  in 
the  other  and  principal  adjustment  of  the  bubble,  we  are 
not  certain  of  placing  the  level-tube  in  the  same  vertical 
plane  ; and  therefore  it  would  be  almost  impossible  to 
effect  the  adjustment  without  a lateral  correction. 

Having  now,  in  great  measure,  removed  the  preparatory 
difficulties,  we  proceed  to  make  the  level-tube  parallel  with 
the  bearings  of  the  Y-rings. 


Engineers * levels. 


163 


To  do  this,  bring  the  bubble  into  the  middle  with  the 
leveling-screws,  and  then,  without  jarring  the  instrument, 
take  the  telescope  out  of  the  Ys  and  reverse  it  end  for 
end.  Should  the  bubble  run  to  either  end,  lower  that  end, 
or,  what  is  equivalent,  raise  the  other  by  turning  the  ad- 
justing-nuts on  one  end  of  the  level  until,  by  estimation, 
half  the  correction  is  made  ; again  bring  the  bubble  into 
the  middle  by  the  leveling- screws,  and  repeat  the  whole 
operation  until  the  reversion  can  be  made  without  causing 
any  change  in  the  bubble. 

It  would  be  well  to  test  the  lateral  adjustment  and 
make  such  correction  as  may  be  necessary  in  that,  before 
the  horizontal  adjustment  is  entirely  completed. 

To  adjust  the  Ys:  Having  made  the  previous  ad- 

justments, it  remains  now  to  bring  the  level  into 

YS 

^ position  at  right  angles  with  the  vertical  axis,  so 
that  the  bubble  will  remain  in  the  middle  during  an  entire 
rotation  of  the  instrument. 

To  do  this,  bring  the  level-tube  directly  over  the  mid- 
dle of  the  bar  and  clamp  the  telescope  in  the  Ys,  placing 
it  as  before,  over  two  of  the  leveling-screws,  unclamp  the 
socket,  level  the  bubble,  and  turn  the  instrument  half-way 
around,  so  that  the  level-bar  may  occupy  the  reverse  position 
with  respect  to  the  leveling-screws  beneath. 

Should  the  bubble  run  to  either  end,  bring  it  half-way 
back  by  the  Y-nuts  on  either  end  of  the  bar  ; then  move 
the  telescope  over  the  other  set  of  leveling-screws,  bring 
the  bubble  again  into  the  middle,  and  proceed  as  above 
described,  changing  to  each  pair  of  screws  successively  un- 
til the  adjustment  is  very  nearly  perfected,  when  it  may  be 
completed  over  a single  pair. 

The  object  of  this  approximate  adjustment  is  to  bring 
the  upper  plate  of  the  leveling-head  into  a position  as 


164 


ENGINEERS'  LEVELS. 


nearly  horizontal  as  possible,  in  order  that  no  essential 
error  may  arise  in  case  the  level,  when  reversed,  is  not 
brought  opposite  its  former  position.  When  the  level 
has  been  thus  completely  adjusted,  if  the  instrument  is 
properly  made  and  the  socket  well  fitted,  the  bubble  will 
reverse  over  each  pair  of  screws  in  any  position. 

Should  the  engineer  be  unable  to  make  it  work  cor- 
rectly, he  should  examine  the  outside  socket  carefully  to  see 
that  it  is  set  securely  in  the  main  socket,  and  also  notice  that 
the  clamp  does  not  bear  upon  the  ring  which  it  encircles. 

When  these  are  correct,  and  the  error  is  still  manifested, 
it  will  probably  be  found  in  the  imperfection  of  the  interior 
spindle. 

After  the  adjustments  of  the  level  have  been  made,  and 
the  bubble  remains  in  the  middle  in  any  position  of  the 
socket,  the  engineer  should  turn  the  telescope  in  the  Ys 
until  the  pin  on  the  clip  of  the  Y will  enter  the  little 
recess  in  the  ring  to  which  it  is  fitted,  and  by  which  is 
insured  the  horizontal  position  of  the  cross-wire. 

When  the  pin  is  in  its  place  the  horizontal  wire  may  be 
applied  to  any  level  line,  and  in  case  it  should  not  be 
parallel  with  it,  two  of  the  cross-wire  screws  that  are  at 
right  angles  with  each  other  may  be  loosened  and,  by  the 
screws  outside,  the  cross-wire  ring  turned  until  the  wire  is 
horizontal  ; the  line  of  collimation  must  then  be  corrected 
again  and  the  adjustments  of  the  Level  will  be  complete. 

TO  USE  THE  LEVEL. 

When  using  the  instrument,  the  legs  of  the  tripod  must 
be  set  firmly  into  the  ground  ; the  bubble  should  then  be 
brought  over  each  pair  of  leveling-screws  successively  and 
leveled  in  each  position,  any  correction  being  made  in  the 
adjustments  which  may  appear  necessary. 


ENGINEERS'  LEVELS. 


165 


Care  should  be  taken  to  bring  the  wires  precisely  in 
focus,  and  the  object  distinctly  in  view,  so  that  all  errors  of 
parallax  may  be  avoided. 

In  all  instances,  the  wires  and  object  should  be  brought 
into  view  so  perfectly  that  the  cross- wires  will  appear  to  be 
fastened  to  the  surface,  and  will  remain  in  that  position 
however  the  eye  is  moved. 

In  running  levels  it  is  best>  wherever  possible,  that 
equal  fore-sights  and  back-sights  should  be  taken,  so  as  to 
avoid  any  error  arising  from  the  curvature  of  the  earth. 

If  the  socket  of  the  instrument  becomes  so  firmly  set  in 
the  leveling-head  as  to  be  difficult  of  removal  in  the 
ordinary  way,  the  engineer  should  place  the  palm  of  his 
hand  under  the  Y-nuts  at  each  end  of  the  bar  and  give  a 
sudden  upward  blow  to  the  bar,  taking  care  also  to  hold  his 
hands  so  as  to  grasp  it  the  moment  it  is  free. 

If  there  is  any  roughness  in  the  movement  of  the 
object-glass  slide,  it  may  be  looked  for  in  three  places  : 

1.  Remove  the  four  little  screws  that  attach  the  pinion- 
strap  to  the  telescope.  See  that  the  pinion  turns  freely  in  its 
socket ; if  it  does  not,  then  there  is  dirt  in  the  bearing  that 
is  cutting  its  surface.  Remove  the  nut  at  the  end  of  the 
pinion-rod  and  knock  the  pinion  out  of  its  head  with  a 
block  of  wood.  The  scratched  surface  can  be  rubbed 
smooth  with  the  back  of  a knife-blade.  Put  a little  tallow 
on  the  bearings  and  replace  the  parts. 

2.  While  the  pinion  is  out  see  that  the  slide  moves 
freely  in  or  out.  If  it  scratches,  rub  it  smooth. 

3.  If  the  pinion  movement  and  slide  are  found  in 
good  order,  the  trouble  may  be  found  on  the  slide  of 
the  slot  opposite  the  rack,  on  the  edge  which  bears  upon 
the  back  of  the  pinion-socket.  Rub  it  smooth  and  apply 
a little  tallow. 


166 


ENGINEERS'  LEVELS. 


# We  have  introduced  in  the  object-glass  slides  of  all 
our  telescopes,  as  well  as  in  the  pinion-sockets,  an  anti- 
friction bearing  which,  after  a trial  of  several  years,  has 
proved  to  be  a complete  remedy  for  the  abrasion  or  fretting 
of  the  surface  above  mentioned. 


NO.  378. 


15-INCH  Y-LEVEX,.  Price  as  shown,  with  tripod,  $90.00. 

Our  fifteen-inch  Level,  as  shown,  has  the  same  arrange- 
ment of  sockets,  tripod,  etc.,  as  the  larger  Levels,  but  has  no 
pinion  movement  to  the  eyepiece.  The  shade  to  the  object- 
glass  is  removable.  The  leveling-head  remains  attached 
to  the  spindle,  and  is  packed  with  it  in  the  box.  The 
instrument  is  also  somewhat  smaller  and  lighter  than  the 
other  sizes. 


ARCHITECTS'  LEVELS . 


167 


SIZE  The  average  weight  of  the  different 

and  weight,  sizes  of  our  Y-Levels,  exclusive  of  the 
tripod,  is  about  as  follows  : 


22-inch  telescope,  with  leveling-head 14  J lbs. 

20-inch  “ “ 13 \ lbs. 

18-inch'  “ “ 13  J lbs. 

15-inch  “ “ Ilf  lbs. 

Architects’  Level,  “ 6J  lbs. 


THE  ARCHITECTS'  LEVEL. 


NO.  380. 

Price  as  shown,  with  tripod,  $50.00. 


The  figure  represents  a Level,  introduced  by  us  in  1874, 
which  is  very  largely  used  by  Architects,  Builders  and  Mill- 
wrights, as  well  as  by  Engineers  and  Surveyors,  in  the 
grading  of  streets,  drains  and  sewers. 

The  instrument  has  a telescope  twelve  inches  in  length, 
furnished  with  rings  and  Ys  like  the  larger  Levels,  and 
adjusted  in  the  same  manner. 


168 


ARCHITECTS'  LEVELS. 


The  leveling-head  has  the  ordinary  screws  and  clamp  to 
the  spindle,  but  no  tangent  movement  ; it  has  also  a hori- 
zontal circle  three  inches  in  diameter,  fitted  to  the  upper 
end  of  the  socket  and  turning  readily  upon  it  ; the  circle  is 
graduated  to  degrees,  figured  from  0 to  90  each  way,  and  is 
read  to  five  minutes  by  a vernier  which  is  fixed  to  the 
spindle.  # 

The  telescope  is  directed  to  any  object  by  hand,  the 
spindle  turning  readily  in  its  socket ; but  it  can  be  clamped 
in  any  position  by  the  clamp-screw  shown  under  the  circle. 

The  instrument  is  placed  either  upon  a light  tripod  as 
shown,  or  on  a small  triangular  plate,  called  a “ trivet,” 
having  three  sharp  steel  points  by  which  it  is  firmly 
set  upon  any  surface  of  wood  or  stone  ; both  tripod  and 
trivet  are  furnished  with  the  Level.  A short  piece  of  tube 
called  a shade  is  also  supplied,  to  put  on  over  the  object- 
glass  to  protect  it  from  the  glare  of  the  sun. 


NO.  381. 

Price  as  shown,  with  clamp  and  tangent  to  spindle,  |65.00. 


ARCHITECTS'  LEVELS. 


169 


< We  add  to  the  Architects’  Level,  when  desired,  a clamp 
and  tangent  movement  on  the  leveling-head,  thus  enabling 
the  instrument  to  be  clamped  more  securely,  and  a move- 
ment in  a horizontal  plane  to  be  made  more  accurately. 
When  thus  fitted,  the  Architects’  Level  is  sold  for  $65.00. 

The  adjustments  of  the  Architects’  Level  are  made  ex- 
actly as  described  in  our  account  of  the 

ADJUSTMENTS,  i t i t-u  . r k, 

larger  Levels.  They  are  not  liable  to 

derangement,  and  will  ordinarily  require  but  little  attention. 

TO  USE  THE  ARCHITECTS'  LEVEL. 

The  instrument  should  be  set  up  firmly  upon  the  tripod 
or  trivet,  and  in  a position  as  nearly  level  as  practicable, 
the  telescope  placed  over  either  pair  of  leveling-screws,  and 
the  bubble  brought  into  the  middle  by  turning  the  opposite 
screws  with  the  thumb  and  forefinger  of  each  hand,  the 
thumbs  being  both  turned  in  or  out  as  may  be  needed,  and 
both  screws  brought  to  a bearing  in  the  little  cups  under- 
neath. Having  brought  the  bubble  into  the  middle  of  the 
vial,  turn  the  telescope  over  the  other  pair  of  screws,  and 
repeat  the  same  operation. 

The  instrument  having  thus  been  carefully  leveled, 
bring  the  eyepiece  and  object-glass  into  focus  upon  the 
object  as  before  described,  and  the  horizontal  cross-wire 
will  give  any  number  of  points  required,  which  will  all  be 
in  the  same  level  plane. 

A strip  of  board  held  erect  will  answer  as  a rod,  and  a 
line  in  pencil  drawn  across  it  at  the  part  cut  by  the  horizon- 
tal wire  will  give  the  height  of  the  starting-point  ; and  any 
different  points  on  the  rod,  either  above  or  below  that 
indicated  by  the  cross-wire,  will  show  the  difference  in 
height  of  the  various  points  assumed,  as  compared  with  the 
starting-point. 


170 


ARCHITECTS'  LEVELS. 


In  laying  off  angles  with  the  Level,  the  bubbles  should 
first  be  brought  into  the  middle  as  before  described,  and 
laying  off  vertical  cross-wire  made  to  cut  the  object 
angles.  or  line  from  which  the  angle  is  to  be  taken. 
Then,  the  spindle  being  clamped  by  the  little  milled  head 
screw  under  the  circle,  the  circle  is  turned  around  by  hand 
until  the  zero-lines  of  both  circle  and  vernier  are  made  to 
coincide  ; then  loosen  the  clamp- screw,  turn  the  telescope 
to  the  point  desired,  and  the  angle  between  the  two  points 
will  be  read  off  on  the  circle. 

The  point  underneath  the  Level  is  easily  indicated  by 
the  point  of  the  plummet  suspended  from  the  tripod. 

It  will  be  understood  that,  by  the  use  of  the  vernier, 
angles  can  be  read  on  the  circle  to  five  minutes,  but 
ordinarily  only  even  angles  will  be  taken  and  only  the 
middle  line  of  the  vernier  will  be  used. 

In  many  situations,  after  the  walls  of  a building  have 
been  carried  up  to  any  required  height,  it  becomes  difficult 
to  set  up  the  tripod,  and  in  this  case  the 
level  is  screwed  upon  the  trivet,  which 
can  be  set  upon  the  wall  or  a piece  of 
board  tacked  to  the  building,  or  indeed 
upon  any  surface  nearly  level  and  not  less 
than  six  inches  square. 

To  illustrate  the  value  of  this  instru- 
ment in  laying  out  the  sites  of  buildings, 
suppose  it  is  desired  to  erect  a 
building,  C D,  at  right  angles 
with  a building,  A B,  and  at  a 
given  distance  from  its  front. 

H First  set  up  the  Level  at  E, 
and  carefully  center  the  bubble,  the  point  of  the  plummet 
below  indicating  the  required  distance  of  the  side  of  the 


ARCHITECTS'  LEVELS. 


171 


new  building  from  the  front,  A B.  Measure  the  same  dis- 
tance at  the  other  corner  of  A B,  and,  having  erected  the  rod, 
sight  upon  it  with  the  telescope  and  clamp  to  the  spindle. 

Now  carry  the  rod  the  required  distance  from  B,  and 
move  it  from  side  to  side  until  it  is  again  in  line  with  the 
telescope,  as  at  C. 

Remove  the  instrument,  and  having  carefully  set  it  over 
the  point,  C,  by  the  plummet  and  brought  the  bubble  into 
the  middle  as  before,  set  the  telescope  again  upon  the  rod 
placed  at  E or  F,  and  clamp  to  the  spindle.  Bring  the 
zeros  of  the  circle  and  vernier  to  coincide,  unclamp,  and 
turn  the  vernier  to  ninety  degrees  ; this  will  give  a point,  D, 
at  any  required  distance  from  C,  and  C D will  be  the  side  of 
the  proposed  building.  The  side,  C G,  is  determined  by 
turning  the  telescope  around  until  the  vernier  is  in  line 
with  the  other  zero  of  the  circle,  and  thus  the  corner,  C,  and 
the  two  sides,  C D and  C G,  are  at  once  set  off,  and  the  re- 
maining corner,  H,  easily  ascertained  by  making  D H and 
G H equal  to  C G and  C D respectively. 

Other  uses  of  the  level,  as  the  setting  of  floor-timbers, 
of  window  and  door -sills,  the  leveling  of  floors,  etc.,  will 
readily  occur  to  one  who  has  been  engaged  in  building, 
where  it  is  of  great  advantage. 

To  the  millwright  such  a Level  is  almost  indispensable 
in  the  lining  and  leveling  of  shafting,  the  ascertaining  of 
the  fall  of  water  obtainable,  and  in  determining  the  over- 
flow of  land  by  a mill-pond. 

The  farmer  will  find  it  of  value  in  laying  out  drains, 
determining  their  location,  ascertaining  the  height  of 
springs,  and  similar  work. 

This  Level  has  become  widely  known,  and  its  extreme 
cheapness,  simplicity  and  excellence  have  created  a great 
demand  for  it. 


172 


DRAINAGE  LEVEL. 


NO.  387. 

Price  as  shown,  $25.00. 


THE  DRAINAGE  LEVEL.  (New  Pattern.) 

Figure  No.  387  represents  a Level  combining  the  ex- 
tremes of  simplicity  and  compactness  with  real  efficiency, 
and  at  a very  moderate  cost.  The  telescope  is  about  nine 
inches  long,  and  is  made  especially  for  this  instrument, 
achromatic,  of  low  but  sufficient  power,  and  good  light 
and  definition.  The  cross-wires  are  fixed  in  the  eyepiece 
so  that  they  are  not  easily  disturbed.  The  level,  telescope 
and  socket  are  enclosed  and  secured  in  a strong  outside  case 
of  brass,  about  seven  and  one-half  inches  long,  two  and 
one-quarter  inches  wide,  and  one  and  one-half  inches  high. 

The  ends  of  the  case  are  thickened  and  made  parallel 
each  to  each,  on  the  upper  and  under  sides. 

A ball  attachment  screws  into  a spindle  that  is  within 
the  case,  and  by  which  it  is  made  approximately  level,  and 
then  precisely  so  by  the  leveling-screws  as  shown. 


DRAINAGE  LEVEL. 


173 


When  desired,  the  leveling-head  can  be  dispensed  with, 
and  the  instrument  leveled  by  the  ball  alone. 

A Compass  with  three-inch  needle  is  added  to  the 
Drainage  Level,  when  desired.  This  is  fitted  securely  to  the 
upper  surface  of  the  case  and  can  be  removed  at  pleasure  ; 
and  while  it  does  not  interfere  in  any  way  with  the  reading 
of  the  level-vial,  it  furnishes  a ready  means  of  determining 
the  bearing  of  lines  or  of  measuring  angles  by  the  needle. 


This  Level  is  adjusted  almost  as  simply  as  an  ordinary 
Masons’  or  Builders’  Level : The  spirit-level,  by  reversing 

from  end  to  end  on  the  lower  faces  of 

ADJUSTMENTS.  . u a ^ ' 

the  case,  and  making  necessary  correc- 
tions by  the  screws  at  the  eyepiece  end,  marked  “ L ” on 
opposite  faces  and  in  line  with  the  level-tube  ; the  tele- 
scope, by  applying  the  opposite  faces  to  the  same  surface, 
and  bringing  the  telescope  cross-wires  by  two  screws 
marked  “ T,”  one  on  each  face,  so  as  to  cut  the  same  point 
in  both  positions  of  the  case.  A small  block  of  wood, 
having  a screw-thread  that  fits  the  top  of  the  ball  attach- 
ment, is  furnished  with  the  instrument,  for  use  in  making 
the  above  adjustments  when  needed.  When  the  ball  is 
screwed  firmly  to  the  spindle,  and  the  instrument  leveled 
up,  it  should  remain  level  when  reversed  upon  its  spindle 
in  any  direction.  If  it  does  not,  correct  the  error  by  the 
two  screws  found  on  the  opposite  sides  of  the  case  and 
marked  “S.”  Should  the  cross-wires  be  indistinct  or  out  of 


174 


DRAINAGE  LEVEL. 


focus,  unscrew  the  cap  of  the  eyepiece,  and  turn  the  set- 
ting of  the  lens  around  in  either  direction  until  the  wires 
are  clearly  seen,  when  the  cover  may  be  replaced  as  before. 
To  clamp  the  instrument  on  the  spindle,  turn  the  small 
milled-head  screw  at  the  eyepiece  end. 

To  screw  the  ball  attachment  to  the  spindle,  press  in 
the  spring-catch  at  the  bottom  of  the  case,  and  the  ball  can 
then  be  easily  screwed  in. 

It  will,  of  course,  be  understood  that  these  adjustments 
are  always  made  by  the  maker,  and  are  not  liable  to  derange- 
ment in  the  ordinary  use  of  the  Level. 

The  advantages  of  this  Level,  in  the  work  of  the 
farmer,  manufacturer  and  builder,  will  be  apparent  on  a 
simple  inspection  : drains  can  be  located  and  leveled,  the 
height  of  springs  ascertained,  and  the  accurate  levels  of 
lines  of  shafting,  floor-timbers  and  sills  be  determined. 

The  Architects’  Leveling-Rods,  hereafter  described,  are 
intended  fot  use  with  this  instrument,  if  desired. 


PRICES. 

No.  Price. 

385.  Drainage  Level,  with  staff  mountings $15.00 

386.  “ “ with  plain  tripod 20.00 

387.  “ “ with  tripod  and  leveling-screws 25.00 


388.  “ “ with  tripod  and  leveling- screws,  and  with 

Compass  and  clamp -screws 


30.00 


TRIPODS. 

LEATHER  CASES  AND  POUCHES. 
LEVELING-RODS. 

RANGING-POLES. 

ROD-LEVEL. 

PLANE-TABLES. 

ALIDADES. 

BATSON  SKETCHING  CASE. 

CURRENT-METERS. 

HAND-LEVELS. 

CHAINS.  • 


TAPES. 


TRIPODS. 


TN  THE  tripods  of  all  our  instruments  the  upper  part  of 
. the  leg  is  flattened  and  slotted  to  fit  closely  on  each 
side  of  a strong  tenon  projecting  from  the  under  side  of 
the  tripod  head,  there  being  also  a strong  brass  bolt,  with 
large  head  and  thumb-nut  on  opposite  sides  of  the  leg,  by 
which  it  is  held  firmly  in  place. 

The  tripod  head  is  made  of  the  best  bell-metal,  the 
tenons  and  upper  part  being  cast  in  one  piece  and  firmly 
braced  together.  The  legs  are  round,  and  taper  in  each 
direction  towards  the  head  and  point. 

The  point  or  shoe  is  a tapering  brass  ferrule,  having  an 
iron  end  ; it  is  cemented  and  firmly  riveted  to  the  wood. 

The  legs  of  all  our  tripods  are  made  of  straight-grained 
hardwood  about  four  feet  eight  inches  long  from  head  to 
point.  We  make  four  sizes  of  tripods  with  solid  legs,  as 
follows  : 

The  heavy  tripod,  No.  400,  has  a metal  head  four  and 
one-quarter  inches  in  diameter,  with  legs  one  and  three- 
eighths  inches  in  diameter  at  the  top,  one  and  three-quarters 
at  the  swell,  and  one  and  one-eighth  near  the  point.  This 
is  used  with  the  Engineers’  Transit  and  with  the  larger 
Y-Levels. 

The  medium  size  tripod  has  a head  of  the  same  diameter 
as  the  former,  and  legs  which  are  one  and  one-eighth  inches 
in  diameter  at  the  top,  one  and  five-eighths  at  the  swell, 
and  one  and  one-sixteenth  near  the  point.  This  tripod  is 
used  with  the  Surveyors’  Transit,  the  light  Engineers’ Tran- 
sit, and  the  fifteen-inch  Level. 

The  Compass  tripod,  No.  415,  has  a head  about  three 
inches  in  diameter,  and  legs  which  are  about  one  inch  in 

176 


TRIPODS. 


177 


diameter  at  the  top,  one  and  three-eighths  at  the  swell,  and 
seven-eighths  near  the  point. 

This  tripod  is  used  with  the  various  Compasses  and 
with  the  Vernier  Transit  Compass. 


PLAIN  TRIPODS . 


178 


TRIPODS. 


The  Pocket-Compass  Tripod  is  the  same  style  as  No. 
415,  but  has  smaller  head  and  legs.  The  legs  are  nearly 
three-quarters  of  an  inch  in  diameter  at  the  top  and  bot- 
tom, and  one  and  one-eighth  at  the  swell. 


SPLIT-LEG  TRIPOD. 

The  improved  split- 
leg  tripod  is  shown  in 
the  engraving.  The 
change  in  form  is  shown 
in  section  at  A B. 

The  legs  are  of 
straight-grained  hard- 
wood, and  by  the  new 
form  stiffness  and 
strength  are  gained  with 
reduced  weight  and 
greater  comfort  in  car- 
rying. We  are  confi- 
dent that  engineers  will 
regard  these  changes  as 
great  improvements. 

We  make  several 
sizes  of  this  tripod,  to 
use  with  Transits, Levels, 
and  Compasses. 


NOS.  405  AND  435- 


TRIPODS . 


179 


EXTENSION  TRIPOD. 

In  No.  410  is  shown 
a decided  improvement 
on  the  old  pattern  of  ex- 
tension tripod,  which  has 
proved  so  popular.  This 
new  tripod  is  stronger, 
more  rigid  and  weighs 
less  than  the  old  form. 

The  difference  is 
shown  in  section  at  A B. 
The  new  tripod  can  be 
carried  with  more  com- 
fort than  the  old,  and 
the  shape  of  the  side 
pieces  allows  the  mid- 
dle piece  to  be  clamped 
firmly  with  the  two 
bands  and  screws,  while 
slight  changes  in  length 
can  be  made  by  twist- 
ing the  middle  piece 
up  or  down.  The  legs 
are  clamped  to  the  tri- 
pod head  with  thumb- 
nuts. 

We  make  several  sizes  of  extension  tripods.  The  large 
size  is  used  with  the  large  Transits  and  Levels,  and  the 
medium  size  with  the  Mountain  Transit.  A smaller  size 
is  used  with  the  smaller  Transits,  Architects’  Levels  and 
large  Compasses,  and  the  smallest  size  is  used  with  the 
various  Pocket-Compasses. 

Note. — For  prices  of  plain,  split-leg  and  extension  tripods,  see  pages 
267  and  268  of  the  Price-List. 


180 


LEATHER  CASES. 

LEATHER  CASES  AND  POUCHES. 


NO.  490. 


We  have  in  our  establishment  the  best  facilities  for 
making  all  kinds  of  leather  work  to  order,  and  can 
promptly  furnish  anything  in  the  line  of  cases  or  pouches 
for  surveying-instruments. 

The  small  pouch  as  shown  in  the  cut  furnishes  a very 
convenient  method  for  carrying  small  Pocket-Compasses 
without  telescopes,  as  Nos.  288—350. 

These  pouches  are  strongly  made,  furnished  with  ad- 
justable sling  strap,  and  are  so  arranged  as  to  hold  the 
Compass  and  its  mountings  firmly  and  protect  them  from 
any  injury  in  transportation.  The  wooden  box  in  which 
the  small  Compasses  are  packed  is  omitted  when  the  leather 
pouch  is  used.  The  leather  cases,  however,  are  fitted  to 
hold  the  wooden  box  containing  the  instrument,  and  are 
used  with  any  Transit,  Level,  or  Compass. 

Note.— For  prices  of  leather  cases  and  pouches,  see  page  269  of  the 

^We  also  make,  to  order,  canvas  cases  for  carrying  tripods  and 
leveling-rods. 


LEVELING -RODS. 


\ 1 TE  GIVE  on  the  following  pages  cuts  and  descriptions 
v ^ of  the  leveling-rods  commonly  used  by  American 
engineers  and  surveyors,  which  are  manufactured  by  us  in 
large  quantities  and  kept  constantly  in  stock. 

Our  facilities  for  the  manufacture  of  leveling-rods  have 
for  many  years  surpassed  those  of  all  other  makers.  The 
greatest  care  is  exercised  in  the  preparation  and  seasoning 
of  the  wood,  special  appliances  and  machinery  for  the  work 
have  been  constructed  at  great  cost,  and  in  point  of  finish 
and  accuracy  our  rods  are  unexcelled. 

For  many  years  wTe  have  made  to  order  special  rods,  to 
special  designs  furnished,  which  have  been  used  in  the 
rods.  most  critical  work  with  perfect  satisfaction. 
We  are  prepared  to  make  rods  of  any  design  to  order. 

THE  PHILADELPHIA  ROD. 

(No.  500.) 

This  rod  is  made  in  two  parts,  each  about  three-quarters 
of  an  inch  thick  by  one  and  one-half  inches  wide  and  seven 
and  three-tenths  feet  long,  the  parts  connected  by  two 
metal  sleeves,  the  upper  one  of  which  has  a clamp-screw  for 
fastening  the  two  parts  together  when  the  rod  is  raised  for 
a higher  reading  than  seven  feet. 

Both  sides  of  the  back  strip  and  one  side  of  the  front  are 
recessed  one-sixteenth  of  an  inch  below  the  edges.  These 
surfaces  are  painted  white,  graduated  into  feet,  tenths  and 
hundredths  of  a foot,  and  the  feet  and  tenths  figured. 

The  graduations  and  figures  are  slightly  impressed  on 
the  recessed  surfaces,  thus  increasing  their  durability. 

181 


182 


LE  VELING-RODS. 


The  edges  of  the  rod  and  the  corners  of 
the  brass  mountings  are  rounded,  for  ease  in 
handling. 

The  front  piece  reads  from  the  bottom 
upward  to  seven  feet,  the  foot  figures  being 
red  and  the  tenth  figures  black.  When  the 
rod  is  extended  to  full  length  the  front  sur- 
face of  the  rear  half  reads  from  seven  to 
thirteen  feet,  and  the  whole  front  of  the  rod 
is  figured  continuously  and  becomes  a self- 
reading roc'  thirteen  feet  long,  reading  to 
hundredths  ot  a foot. 

The  back  surface  of  the  rear  half  is 
figured  from  seven  to  thirteen  feet,  reading 
from  the  top  down  ; it  has  also  a scale  by 
which  the  rod  is  read  to  hundredths  and  half- 
hundredths of  a foot  as  it  is  extended.  The 
target  is  round,  made  of  brass  raised  on 
the  perimeter  to  increase  its  strength,  and  is 
painted  in  white  and  red  quadrants  ; it  has 
also  a scale  on  its  chamfered  edge,  reading 
to  half-hundredths  of  a foot. 

Both  of  these  scales  should  be  read  from  the 
top  of  the  next  preceding  tenth  mark  on  the 
rod,  remembering  that  they  are  not  verniers. 

When  a level  of  less  than  seven  feet  is 
desired  the  target  is  moved  up  or  down  the 
front  surface,  the  rod  being  closed  and 
clamped  ; but  when  a greater  height  is  re- 
quired the  target  is  fixed  at  seven  feet  and  the 
rear  half  extended,  the  scale  on  the  back  giv- 
ing the  readings  like  those  of  the  target  to 
half-hundredths  of  a foot. 


LEVELING- RODS. 


183 


THE  BOSTON  ROD. 

(No.  603.) 

This  rod  is  formed  of  two  pieces,  each 
about  six  feet  long,  sliding  easily  by  each 
other  in  either  direction. 

One  side  is  furnished  with  a clamping  piece 
and  screw,  with  a small  vernier  at  each  end  •; 
the  other  or  front  piece  carries  the  target,  and 
has  on  each  side  an  inlaid  strip  upon  which 
graduations  of  feet,  tenths  and  hundredths  are 
marked  and  figured. 

The  target  is  a disk  of  brass  raised  on  its 
perimeter,  fastened  on  the  front  half,  and  is 
painted  red  and  white,  having  its  middle  line 
just  three-tenths  of  a foot  from  the  end  of  the 
rod. 

Each  tenth  graduation  is  figured  decimally 
in  three  figures,  or  to  hundredths  of  a foot, 
and  by  the  verniers  is  read  to  thousandths. 

The  target  being  fixed,  when  any  height  is 
taken  above  six  feet,  the  rod  is  changed  end 
for  end  and  the  graduations  read  by  the  other 
vernier,  the  height  to  which  the  rod  can  be  ex- 
tended being  a little  over  eleven  feet. 

This  rod  is  very  convenient  on  account  of 
its  lightness,  but  the  parts  are  too  frail  to 
endure  the  rough  usage  of  this  country  ; and 
American  Engineers  generally  prefer  other 
rods  which  are  heavier  and  more  substantial. 


504.  TROY  ROD.  Price,  $10.00. 


LEVELING- ROBS. 


THE  TROY  ROD . 
(No.  504.) 


d 

z 


The  cut  represents  another  form  of  the 
sliding  leveling- rod,  called  the  Troy  rod. 
This  is  a self-reading  rod  up  to  six  feet,  or  it 
can  be  read  by  a vernier  on  the  rear  piece  to 
thousandths  of  a foot,  as  usual. 

It  has  two  targets  as  shown,  both  fastened 
to  the  front  half  of  the  rod,  the  lower  one  hav- 
ing its  middle  line  just  three-tenths  of  a foot 
above  the  end,  and  the  other  target  exactly  six 
feet  above  the  lower. 

There  is  a clamping  piece  with  screw  on 
the  back  of  the  rod,  below  the  upper  target, 
by  which  the  two  parts  are  clamped  together 
when  desired. 

The  face  of  the  front  piece  is  recessed  like 
that  of  the  Philadelphia  rod,  painted  white, 
graduated  to  feet  and  hundredths,  and  figured 
as  represented. 

The  side  of  the  front  half  is  graduated  to 
feet  and  hundredths,  read  by  a vernier  on  the 
top  of  the  rear  half  to  thousandths,  and  figured 
from  the  top  downwards,  beginning  with  three- 
tenths,  that  being  the  height  of  the  middle 
line  of  the  lower  target. 

When  a level  of  less  than  six  feet  is  taken 
on  the  rod  the  observation  is  made  by  the 
lower  target,  and  the  reading  is  direct  as  given 
on  the  side  ; but  when  a greater  height  is 
taken  the  upper  target  is  sighted  upon,  and 
six  feet  added  to  the  reading  on  the  side,  a 


LEVELING- RODS,  Jgg 

reading  up  to  twelve  feet  being  thus  readily 
obtained. 

THE  NEW  YORK  ROD . 

( No.  505. ) 

This  rod,  which  is  shown  in  the  engraving 
as  cut  in  two,  so  that  the  ends  may  be  ex- 
hibited, is  made  in  two  parts,  the  pieces  sliding 
one  from  the  other,  the  same  end  being  always 
held  on  the  ground,  and  the  graduations  start- 
ing from  that  point. 

The  graduations  are  made  to  tenths  and 
hundredths  of  a foot,  the  tenth  figures  being 
black,  and  the  feet  marked  with  a large  red 
figure. 

The  front  surface,  on  which  the  target 
moves,  reads  to  six  and  one-half  feet  on  the 
two-part  rods.  When  a greater  height  is  re- 
quired, the  horizontal  line  of  the  target  is  fixed 
at  the  highest  graduation,  and  the  upper  half 
of  the  rod  carrying  the  target  is  moved  out  of 
the  lower,  the  reading  being  now  obtained  by 
a vernier  on  the  graduated  side,  up  to  an  ele- 
vation of  twelve  feet. 

The  target  is  round,  made  of  brass  with  a 
raised  rim  to  strengthen  it  and  to  protect  the 
paint  from  being  defaced. 

The  target  is  arranged  with  an  improved 
clamp,  which  can  be  so  adjusted  as  to  regulate 
the  friction  on  the  rod,  enabling  the  target  to 
be  easily  moved  up  and  down,  and  to  be 
clamped  with  a slight  turn  of  the  binding- 


screw. 


186 


LE  VELING-RODS. 


The  face  of  the  target  is  graduated  Into 
quadrants  by  horizontal  and  vertical  diam- 
eters, the  quadrants  being  painted  alter- 
nately white  and  red,  or  sometimes  white  and 
black. 

The  opening  in  the  face  of  the  target  is 
nearly  two-tenths  of  a foot  long,  so  that  in 
any  position  a figure  noting  a tenth  of  a foot 
can  be  seen  on  the  surface  of  the  rod. 

The  right  edge  of  the  opening  is  cham- 
fered, and  graduated  into  ten  equal  spaces  cor- 
responding with  nine  hundredths  on  the  rod. 
The  graduations  start  from  the  horizontal  line 
which  separates  the  colors  of  the  face. 

The  vernier,  like  that  on  the  side  of  the 
rod,  reads  to  thousandths  of  a foot.  The  rod 
is  fitted  with  the  improved  clamp. 

THE  NEW  YORK  ROD . 

In  three  or  four  parts.  (Nos.  507  and  508.) 

( PATENTED.) 

In  this  rod,  as  shown,  a third  or  fourth 
piece  is  added,  giving  a rod  of  a greater 
length,  and  at  the  same  time  making  it  more 
compact  and  portable. 

The  graduations,  verniers  and  readings 
are  the  same  as  those  of  the  rod  in  two  parts. 

The  three-part  rod  allows  a reading  of 
twelve  and  one-half  feet,  and  when  closed  is 
five  feet  long. 

The  four-part  rod  when  closed  is  five 
feet  long,  but  it  can  be  extended  to  sixteen 
feet. 


LE  VELING-RODS. 


187 


THE  ARCHITECTS'  ROD, 

(Nos.  510  and  511.) 

This  is  a very  light  and  simple  sliding  rod 
in  two  equal  parts,  each  seven-eighths  of  an 
inch  square,  and  when  closed  the  rod  is  about 
five  feet  six  inches  long. 

As  shown,  the  front  half  is  graduated  on 
two  sides  to  feet,  tenths  and  hundredths,  read- 
ing by  verniers  on  the  target  and  side  to  thou- 
sandths of  a foot. 

The  target  is  similar  to  those  of  the  rods 
already  described,  and  it  moves  on  the  closed 
rod  when  levels  of  less  than  five  and  four- 
tenths  feet  are  to  be  taken. 

When  a greater  height  is  needed,  the  target 
is  fixed  at  the  highest  graduation,  the  front 
half  carried  above  the  rear  part  and  clamped 
by  the  clamp-screw  at  any  point  desired,  the 
height  up  to  ten  feet  being  now  read  off  by  the 
vernier  on  the  lower  half. 

This  rod  is  adapted  for  use  with  any  Level, 
and  is  so  light  and  efficient  that  it  has  been 
received  with  favor.  It  is,  however,  generally 
used  with  the  Architects’  and  Drainage  Levels. 

When  it  is  designed  for  Architects’  use  the 
graduations  are  in  feet,  inches  and  sixteenths, 
and  no  vernier  is  required. 


188 


LEVELING-RODS. 


r 


V 


THE  MACHINISTS'  ROD . 

(No.  512.) 

The  Machinists’  rod  is  made  in  one 
piece  with  a cross-section  about  seven- 
eighths  of  an  inch  square  and  a length 
of  six  and  one-half  feet,  and  is  gradu- 
ated on  one  face  to  feet,  inches  and  six- 
teenths. At  one  end  and  attached  to 
the  rod  with  a swivel  is  a large  hook  by 
which  the  rod  may  be  hung  from  a shaft. 
The  target  is  painted  red  with  broad 
white  lines  crossing  the  center  and  is 
fitted  with  candle-holder.  This  rod  is 
designed  especially  for  use  in  leveling 
shafting  in  factories  and  in  conjunction 
with  the  Architects’  Level  will  be  found 
most  serviceable. 

THE  TELEMETER  ROD . 

(No.  513.) 

The  Telemeter,  or  Stadia,  rod  is 
formed  of  two  pieces  of  pine,  each  three 
and  one-half  inches  in  width  and  six  feet 
long.  The  inner  surfaces  of  the  rod  are 
recessed  to  protect  the  graduated  sur- 
face, and  painted  white,  with  gradua- 
tions in  black  to  feet,  tenths  and  hun- 
dredths, the  feet  figured  in  red  and  the 
tenths  in  black.  The  two  pieces  are  con- 
nected by  strong  brass  hinges  and  folded 
in  transportation.  When  in  use  they  are 
opened,  laid  flat  and  held  firmly  in  line 


NO.  513.— TELEMETER  OR  STADIA  ROD.  Price,  $12.00. 


LE  VELING-RODS. 


189 


by  a strong  brass  clip  on  the  back  of  the  rod. 
The  rod  tapers  toward  the  top  from  a thickness 
at  the  bottom  of  one  and  one-eighth  inches. 
This  is  a self-reading  rod,  and  is  often  used  in 
connection  with  the  stadia  to  ascertain  dis- 
tances by  simple  observation,  in  the  same 
manner  as  the  Philadelphia  rod  already  de- 
scribed. The  price  is  $12.00. 


THE  TELESCOPIC  ROD . 

(No.  515.) 

This  rod  is  made  so  that  the  two 
smaller  upper  parts  slide  out  of  a larger 
and  lower  part  which  answers  as  a case. 
When  closed  the  rod  is  five  feet  long, 
and  it  extends  to  fourteen  feet.  It  is 
graduated  on  a recessed  face  to  feet, 
tenths  and  hundredths,  the  gradua- 
tions being  painted  and  figured  like 
those  of  the  Philadelphia  and  Tele- 
meter rods. 

THE  CROSS-SECTION  ROD . 

(No.  516.) 

This  rod  is  made  of  well-seasoned 
pine,  and  is  ten  feet  long  and  one  and 
one-half  inches  square  at  the  ends  ; it 
is  about  four  inches  thick  in  the  mid- 
dle, where  there  is  arf  opening  for  the 
hand,  as  shown.  Both  sides  are  gradu- 
ated on  a recessed  white  surface,  the 
graduations  being  painted  black  like 
those  of  a leveling-jx>d,  and  figured 


NO.  516.  CROSS-SECTION  ROD.  Price, 810.00. 


190 


LEVELING-RODS  AND  POLES.  . 


from  the  same  end  of  the  rod.  There  is  also  an 
adjustable  spirit-level  at  each  end,  one  of  which  is 
shown  in  the  cut. 


PLAIN  LEVELING-ROD. 
No.  518. 


© 

© 


ft 

0 

P4 

1 

O 

£ 


g 

< 

t-1 

Pu 


00 

IX) 

6 

z 


A very  good  self-reading  rod  is  made  of 
seasoned  white  pine,  recessed  and  graduated 
on  one  face  like  the  Philadelphia  rod.  A rib 
at  the  back,  extending  through  the  length  of 
the  rod,  gives  great  rigidity,  while  it  does  not 
materially  increase  the  weight.  The  plain 
leveling-rod  is  commdnly  made  ten  and  twelve 
feet  long,  but  can  be  made  longer,  if  desired, 
at  an  additional  cost  of  about  fifty  cents  per 
foot.  These  rods  are  also  made  with  a hinge 
joint  at  the  center,  at  an  extra  cost  of  $2.00. 
(See  page  270.) 

METRIC  RODS. 

Besides  the  usual  graduation  of  leveling- 
rods  into  feet  and  parts  of  a foot,  we  gradu- 
ate them,  when  desired,  into  meters,  deci- 
meters and  centimeters.  The  scales  on  the 
targets  and  sides  of  the  rods  read  the  centi- 
meters to  millimeters  on  all  except  the  tele- 
meter, telescopic  and  plain  rods,  which  have 
no  targets  and  are  ^ead  only  to  centimeters. 
The  New  York,  Troy,  Boston  and  Architects’ 
Metric  rods  are  graduated,  when  desired, 
to  read  by  vernier  to  one-tenth  of  a milli- 
meter. 


r 7 

i-6 

r5 

5-* 

^3 


r2 

=-i 


NO. 

53Q. 


FLAG  STAFFS. 


191 


LE  VELING-POLE. 

The  leveling-pole,  shown  in  No.  530,  is  a 
combination  of  a plain  self-reading  rod  and  a 
flagpole.  It  is  made  with  flat  face,  front  and 
rear,  and  rounded  sides.  One  face  is  graduated 
to  feet  and  hundredths  of  a foot,  while  the  other 
face  and  sides  are  graduated  to  feet  only  and 
are  painted  red  and  white  alternately.  The  pole 
is  made  seven  and  nine  feet  long,  the  graduated 
faces  reading  to  six  and  eight  feet  respectively, 
and  when  used  as  a rod  is  read,  as  shown  in  the 
cut.  The  prices  are  $5.00  and  $6.00. 

WOOD  AND  IRON  FLAGS  TAPES. 

We  make  three  sizes  of  the  common  wood 
flagstaffs,  or  ranging-poles.  They  are  octag- 
onal in  form,  tapering  from  the  bottom  to  the 
top,  six,  eight,  and  ten  feet  long,  and  have  steel 
shoes.  (See  cut  No.  534.) 

We  also  make  a convenient  ranging-pole  of 
an  iron  tube,  eleven-sixteenths  of  an  inch  in 
diameter,  hung  in  gimbals  so  that  it  can  be 
readily  set  over  a given  point.  (See  cut  No. 
539.)  Similar  iron  poles  are  made  without  gim- 
bals, six,  eight,  and  ten  feet  long. 

These  staffs  are  graduated  to  feet,  and  paint- 
ed alternately  red  and  white. 

They  are  also  graduated  metrically,  when 
desired,  five  spaces  to  each  meter. 

Note. — For  prices  of  Leveling- Rods  and  Flagstaffs, 
see  pages  270  and  271  of  the  Price-List, 


192 


ROB- LEVEL. 


THE  ROB-LEVEL. 


No.  545  represents  a level  for  the  more  accurate  plumb- 
ing of  leveling-rods  and  ranging-poles.  The  figures  show 
it  when  folded  for  carrying,  and  also  as  attached  to  a rod. 

It  is  held  in  place  by  the  hand,  or  can  be  secured  by  a 
string  or  rubber  band  to  hooks  attached  to  each  plate  of 
the  level.  Its  convenience  and  value  have  commended  it 
to  general  favor. 


CIRCULAR  ROB-LEVEL . 

We  also  make  a Rod-Level  with  circular  level-vial,  fold- 
ing against  the  rod  when  not  in  use.  This  level  is  to  be 
attached  to  the  rod,  and  hence  it  cannot  be  used  where 
there  is  a target  or  clamp-band  to  slide  past  it.  It  is  very 
serviceable  on  self-reading  and  stadia  rods. 

Price  $3.00.  See  No.  546  in  Price-List. 


THE  PLANE-TABLE 


THE  recognized  utility  of  the  Plane-Table  for  topo- 
graphical and  map  drawing  is  bringing  it  into  use  in 
this  country  ; and  to  meet  the  demand  for  instruments, of 
moderate  cost  and  real  efficiency  we  have  introduced  several 
patterns  of  the  Plane-Table. 


No.  NO-  553. 

553.  Plane-Table,  board  30x24  inches,  mounted  on  large  tripod, 
with  leveling-socket  and  clamp,  plumbing-arm,  plum- 
met and  clamps  for  paper * 

Combined  Compass  and  levels - 

Alidade,  with  telescope  9 inches  long,  power  20  diam- 
eters, with  stadia,  vertical  circle  to  1 minute,  level  on 
telescope  and  clamp  and  tangent,  mounted  on  column 
as  in  engraving 

Price  as  shown,  total -t..T. 


Price. 


$45.00 

15.00 

70.00 


193 


$130.00 


194 


PLANE-  TABLES. 


The  Plane-Table  consists  mainly  of  a drawing-board 
upon  a firm  tripod,  as  shown  in  No.  553,  having  upon 
its  upper  surface  a movable  straight-edge  or  Alidade,  ar- 
ranged either  with  sight-vanes  or  telescope,  by  which  it 
may  be  directed  to  any  given  point,  a line  being  then 
drawn  on  the  paper  along  the  edge  of  the  Alidade. 

A square  brass  plate,  to  which  is  attached  a Compass 

with  two  spirit-levels,  is  also  shown,  and  serves  both  to 

level  the  table  and,  when  applied  by  the 
THE  COMPASS.  ’ r c 

edges  parallel  to  the  zero-lines  of  the 

compass-circle,  to  determine  the  magnetic  bearing  of  the 

lines  drawn  on  the  paper,  or  the  direction  of  the  table  itself. 

The  table  is  made  of  wood  arranged  in  sections  so  as  to 
prevent,  warping,  and  has  an  adjustable  wooden  roller 
drawing- at  each  end,  by  which  the  paper  is  brought 
board,  down  snugly  to  the  board  or  upon  which  a long 
sheet  can  be  rolled  and  unrolled  at  will.  Sometimes  in 
place  of  the  rollers,  and  often  in  combination  with  them,  a 
number  of  brass  clamps,  as  shown,  are  used  in  holding  the 
paper  firmly. 

Still  another  method  of  fastening  the  paper  to  the  board 
is  shown  in  the  cut  on  page  197,  in  which  are  represented 
small  brass  screws  passing  through  the  paper  and  into 
brass  sockets  let  into  and  slightly  below  the  surface  of  the 
board.  This  method  allows  the  Alidade  to  move  over  the 
surface  without  interference. 

The  plumbing- arm  shown  in  the  figure  has  its  end 
brought  to  a point,  that  it  may  be  set  at  any  given  point  on 
the  paper,  the  plummet  hanging  from  the 

PLUMBING-ARM.  . ....  .. 

under  arm  determining  the  corresponding 

point  on  the  ground.  The  lower  arm  moves  upon  a hinge, 

an  index  on  the  side  showing  when  the  ends  of  the  two 

arms  are  plumb  with  each  other  as  applied  to  the  table. 


PLANE  - TABLES. 


195 


The  construction  of  the  socket  and  tripod  head  is 
shown  below,  a representing  the  hemispherical  concave 
the  socket  metal  cup  fastened  by  six  screws  to  the 
and  tripod,  wooden  top  of  the  tripod,  b the  upper  or 
convex  part  fitting  nicely  into  the  cup  and  clamped  to  it 
at  will  by  the  clamping  piece,  c,  and  nut,  d.  A strong 
spiral  spring  in  the  hollow  cylinder  between  c and  d serves 
to  hold  the  two  spherical  surfaces  of  the  socket  together 
and  allows  the  easy  movement  of  one  within  the  other  in 
the  leveling  of  the  table. 


The  flange  of  the  socket,  b,  supports  the  table  and  is 
connected  with  it  by  three  segments  of  brass,  two  of  which 
are  shown  at  e e.  The  table  can  be  oriented  at  will  and 
clamped  by  a milled  head  screw  passing  through  one  of 
these  segments. 

PLANE-TABLE  WLTH  LEVELLNG-SCREWS 
AND  TANGENT  MOVEMENT. 

The  cut  on  page  196  shows  a modification  of  the  simple 
Plane-Table,  there  being  added  a tangent  movement  in 
azimuth  and  three  screws  for  leveling. 

The  board  appears  as  if  cut  away,  to  show  in  detail  the 
socket  and  leveling-screws  and  tangent  movement,  by 
which,  as  will  be  seen,  a more  delicate  orienting  may  be 
obtained  than  by  the  simple  movement  before  described. 


196 


PLANE-  TABLES. 


The  Plane-Table  outfit  as  shown  above  is  our  No.  549 

and  costs  as  follows  : 

Prick. 


Plane-Table,  board  30  x 24  inches,  mounted  on  large  tripod,  with  leveling-socket 

and  clamp,  and  with  plumbing-arm,  plummet,  and  clamps  for  paper §45.00 

Set  of  three  leveling-screws 10.00 

Clamp  and  tangent,  for  movement  in  azimuth 10.00 

Combined  Compass  and  levels,  with  square  base 15.00 

Alidade,  with  telescope  11  inches  long,  with  stadia,  41.2-inch  vertical  circle  and 
vernier  to  1 minute,  level  on  telescope  and  clamp  and  tangent,  on  column,  power 
of  telescope  24  diameters. 90.00 


PLANE-TABLES . 


197 


The  tripod  is  set  up  firmly,  and  the  board  with  the 
upper  half  of  the  spherical  socket  attached  is  placed  upon 
using  the  the  lower  half  of  the  socket  attached  to 
plane-table,  the  tripod,  the  wing  clamping  nut  being 
screwed  up  until  the  table  is  secure  upon  the  tripod.  The 
board  is  then  moved  by  the  pressure  of  the  hand,  or  by  the 
leveling-screws,  until  the  level-bubbles  upon  the  compass- 
plate  will  remain  in  the  middle  upon  any  part  of  the  sur- 
face. The  wing-nut  is  now  screwed  up  and  the  board  made 
firm  upon  the  tripod. 

Any  place  on  the  drawing-board  may  then  be  assumed 
as  a starting-point,  its  position  over  a given  point  on  the 
ground  being  determined  by  the  plumbing-arm  and  plum- 
met. From  the  given  point  on  the  paper  sights  can  be 
taken  to  different  corners  of  the  field,  and  lines  drawn  on 
the  paper  along  the  edge  of  the  Alidade.  Thus  a miniature 
of  the  tract  can  be  traced  on  the  paper,  the  bearing  of  any 
line  being  ascertained  by  applying  the  side  of  the  compass- 
plate  to  the  edge  of  the  Alidade  placed  on  that  line.  The 
table  can  be  oriented,  either  by  the  hand,  on  releasing  the 
milled  head  screw  that  clamps  the  flange,  or  by  the  tangent 
screw  as  before  described. 

The  measurement  of  distances  by  the  stadia  wires  of  the 
telescope,  and  of  vertical  angles  by  the  circle,  is  effected  as 
already  described  in  our  account  of  the  Transit. 


198 


PLANE  TABLES. 


JOHNSON'S  IMPROVED  PLANE-  TABLE. 

MOVEMENT. 

(PATENTED.) 

We  illustrate  on  page  199  what  is  known  as  the  John- 
son Plane-Table  Movement,  complete  with  large  Alidade, 
Plumbing- Arm  and  Compass. 

The  board  is  shown  as  cut  away,  to  give  a better  view 
of  the  tripod  and  movement.  In  the  lower  corner  is  shown 
the  movement  alone,  with  a portion  cut  away  to  show  the 
construction. 

This  movement  has  been  largely  used  by  the  topog- 
raphers of  the  U.  S.  Geological  Survey. 

As  shown  in  the  cut,  this  movement  supplies  an  arrange- 
ment whereby  the  table  can  be  easily  made  horizontal  and 
then  secured  by  the  large  wing-nut,  A.  To  orient  the 
board,  the  wing-nut,  B,  is  loosened,  leaving  the  hemispheri- 
cal surface,  bearing  the  board  secured  to  the  flange,  free  to 
turn,  and  it  can  be  clamped  at  will  by  screwing  up  the  same 
nut.  This  movement  as  modified  in  recent  years  supplies 
an  extremely  efficient  and  portable  Plane-Table. 

The  movement  with  legs  complete  weighs  about  nine 
pounds.  The  legs  are  made  of  straight-grained  second- 
growth  hickory,  and  the  construction  of  the  whole  tripod 
is  such  as  to  secure  strength  and  accuracy,  and  it  is 
capable  of  standing  rough  usage  without  getting  out  of 
order. 

Note. — Any  of  the  Alidades,  as  described  on  pages  306-302,  can  be  nsed  -with 

Johnson’s  Plane-Table. 

See  pages  273  and  274  for  a list  of  Johnson’s  Plane-Table  outfits,  with  prices. 


PLANE - TABLES . 


199 


The  Johnson  Plane-Table  outfit  as  shown  above  is  our 


No.  576,  and  costs  as  follows  : 

Price. 

Johnson’s  Improved  Plane-Table  movement,  mounted  on  large  tripod $45.00 

Plane-Table  Drawing-Board  31  x 24  inches,  fitted,  and  with  screw-sockets  and 

clamps  for  paper 5.00 

Plumbing-arm  and  plummet 4.00 

Combined  Compass  and  levels  with  square  base : „ 15.00 

Alidade,  with  telescope  11  inches  long,  with  stadia,  4%-inch  vertical  circle  and 
vernier  to  1 minute,  level  on  telescope  and  clamp  and  tangent,  on  column,  power 
of  telescope  24  diameters 90.00 


Total $159.00 


200 


ALIDADES. 


THE  ALIDADES. 

The  different  patterns  of  our  Plane-Tables  vary  mainly 
in  their  Alidades,  of  which  we  make  several  kinds. 


The  simplest  Alidade  is  shown  above,  and  consists  of  a 
brass  ruler  or  straight-edge,  twenty  inches  long  and  about 
three  inches  wide,  at  the  ends  of  which  sight-vanes  are 
mounted  like  those  on  the  ordinary  compass.  The  edge  of 
the  ruler  is  chamfered  and  in  line  with  the  slots  of  the  vanes. 


NO.  581.  Price,  $50.00. 

The  lower  figure  shows  the  simple  Alidade  to  which  is 
fitted  the  Telescopic  Sight,  having  a level,  clamp  and 
tangent  and  vertical  circle  reading  to  five  minutes,  attached 
to  the  telescope,  which  has  also  stadia  wires.  The  tele- 
scope is  placed  in  line  with  the  fiducial  edge. 


ALIDADES. 


201 


The  third  style  of  Alidade,  No.  582,  is  shown  in  the  cut 
of  the  Plane-Table  on  page  193,  the  brass  ruler  being  three 
inches  wide. 

The  column  supports  the  telescope  with  its  attachments, 
the  vertical  circle  being  graduated  on  silver  and  reading  to 
one  minute. 

The  telescope  is  nine  inches  long,  with  a power  of 
twenty  diameters,  provided  with  stadia  wires  and  adjusted 
like  that  of  the  Transit. 


In  the  Alidade  shown  in  cut  No.  583,  the  telescope  is 
the  same  as  that  used  in  our  best  Transits,  having  also 
level,  clamp  and  tangent,  vertical  circle  on  silver  reading 
to  one  minute,  and  stadia  wires  for  measuring  distances. 

It  is  placed  on  a brass  ruler  four  inches  wide,  and  is 
adjusted  and  used  in  the  same  manner  as  the  one  just 
described. 


202 


ALIDADES. , 


NO.  584. 

Price,  as  shown $118.00. 

Price,  as  shown,  and  with  Compass....  128.00. 


In  Alidade  No.  584,  shown  in  the  cut,  the  blade  is 
eighteen  inches  long  by  three  inches  wide,  and  carries 
a telescope  eleven  inches  long  with  a detachable  striding 
level,  vertical  arc  and  axis  tangent.  For  easy  adjustment 
of  the  line  of  collimation  the  telescope  can  be  turned  in  its 
axis  through  180°.  The  vertical  arc  reads  by  vernier  to 
one  minute  ; and  having  its  zero  at  one  end,  all  the  angles 
read  are  thus  positive.  The  telescope  is  made  either  in- 
verting or  erecting,  as  desired  ; and  when  made  inverting 
it  is  usually  fitted  with  a diagonal  prism,  with  darkener,  as 
shown. 


TRAVERSE  PLANE-TABLE. 


203 


THE  TRAVERSE  PLANE-TABLE. 

.The  cut,  No.  586,  represents  a simple  form  of  Plane- 
Table  and  Alidade,  which  is  used  extensively  by  the  U.  S. 
Geological  Survey  for  traverse  work.  The  board  is  fifteen 
inches  square,  and  has  on  the  under  side  a small  brass 
flange,  into  which  the  clamp-screw  of  the  tripod  head 
enters  and  secures  the  board  to  the  tripod.  The  Alidade 
consists  of  a brass  ruler,  ten  inches  long,  graduated  on  the 


NO.  586. 

Price  as  shown,  $25.00  ; if  the  tripod  has  extension  legs,  add  extra  $5.00. 


beveled  edge  to  a scale  of  forty  parts  to  the  inch,  and 
having  at  each  end  hinged  sights  which  fold  close  to  the 
surface  of  the  ruler.  Inserted  in  one  edge  of  the  board 
is  a small  Box-Compass  with  needle  about  three  inches 
long. 


204 


TRAVERSE  PLANE-TABLE. 


The  tripod  legs  are  attached  to  a simple  head  which 
has  a clamping  screw  passing  through  its  center,  compress- 
ing a concealed  spring  and  holding  the  board  to  the  tripod 
head  when  oriented  to  position. 

The  whole,  while  not  capable  of  as  accurate  work  as 
the  larger  Plane-Tables,  supplies  a light  and  portable  instru- 
ment for  topography. 

POCKET  ALLDADES . 

A pocket  Alidade,  of  pattern  like  the  one  shown  with 
the  Traverse  Plane-Table,  is  made  six  inches  long  and  has 
hinged  sights  which  fold  close  to  the  ruler.  The  beveled 
edge  is  graduated  to  scale  of  one  forty-five  thousandth  and 
one  ninety  thousandth,  each  graduation  representing  one 
twentieth  or  one  fiftieth  of  a mile.  Price,  in  leather 
pouch,  $7.50. 

Another  form  of  the  pocket  Alidade  is  made  seven 
inches  long  and  has  a peep  hole  for  the  near  sight  and  for 
the  other  a folding  sight  graduated  for  a vertical  scale 
representing  a rise  of  twenty-five  feet  to  the  mile.  The 
beveled  edge  is  graduated  the  same  as  the  six-inch  Alidade 
described  above.  The  ruler  carries  an  adjustable  level 
with  knurled  head  leveling-screw.  Price,  in  leather 
pouch,  $12.00.  (See  page  274  of  the  Price-List.) 


. THE  BATSON  SKETCHING-CASE. 


(PATENTED.) 


NO.  595.  Price,  $30.00. 

HP  HE  engraving  shows  the  Batson  Sketching-Case  de- 
* signed  for  the  use  of  Civil  and  Military  Engineers 
and  Surveyors  in  reconnoissance  and  topographical  surveys. 
It  was  given  an  extensive  and  successful  trial,  in  1898  and 
1899,  in  Cuba  and  the  Philippines,  as  well  as  in  the  United 
States. 

This  instrument  is  a small  drawing-board,  having  upon 
its  upper  surface  a movable  graduated  circle,  carrying  a 
small  alidade  with  scales,  and  at  one  end  of  the  board  a 
compass  and  a clinometer. 

The  drawing-board  is  made  of  wood,  and  is  provided 
with  rollers  which  carry  the  paper  for  recording  observa- 
tions. Friction-brakes  hold  the  rollers,  so  that  the  paper  is 
held  down  snugly  to  the  board  and  prevented  from  uncoil- 
ing. 

Six  holes  at  the  end  of  the  board  opposite  the  compass 

205 


206 


BATSON  SKETCHING-CASE. 


afford  receptacles  for  the  pencils  used  in  topographical 
sketching. 

The  protractor  is  held  in  position  by  a carrier  which 
slides  upon  a bar  attached  to  the  wooden  end-pieces 
as  shown.  The  construction  of  the  carrier  allows  the 
protractor  to  be  turned,  or,  if  desired,  to  be  clamped  by 
means  of  two  set-screws. 

The  protractor  can  also  be  lifted  to  an  upright  position 
by  pulling  back  the  spring-catch  at  the  end  of  the  carrier- 
bar. 

The  alidade  turns  within  the  graduated  circle,  and,  with 
it,  forms  the  protractor. 

The  paper  for  use  with  this  instrument  is  six  inches 
wide,  and  thirty  to  forty  inches  is  found  to  be  a convenient 
length. 

The  sketching-case  is  fitted  with  a strap  for  carrying  on 
the  forearm,  and,  if  desired,  is  provided  with  a short,  light 
staff,  or  a tripod,  for  use  in  taking  bearings  on  reference 
points  and  on  objects  which  it  is  desirable  to  locate  with 
more  accuracy  than  can  be  done  by  holding  in  the  hand. 

A sole-leather  case,  having  a pocket  for  the  instrument 
and  another  for  sketches  and  extra  paper,  and  fitted  with 
lock  and  shoulder  strap,  is  provided  with  each  instrument. 

TO  MOUNT  THE  PAPER. 

Raise  the  protractor  to  a vertical  position.  Having  the 
board  with  compass  to  the  right,  insert  one  end  of  the 
paper  in  the  slit  of  the  far  roller  and  turn  the  roller  toward 
the  board  until  only  seven  or  eight  inches  of  the  paper  are 
left  free,  then  insert  the  free  end  in  the  slit  of  the  near 
roller  and  turn  the  roller  toward  the  board  until  the  paper 
is  taut.  Release  the  protractor  and  turn  it  down  on  the 
board. 


BATSON  SKETCHING-CASE. 


207 


TO  SET  THE  INSTRUMENT. 

Release  the  needle.  Face  in  the  general  direction  of 
the  route  to  be  mapped  and  hold  the  instrument  in  the  left 
hand  with  the  compass  to  the  right  ; or,  having  it  set  up  on 
the  staff,  orient  it  until  the  long  way  of  the  paper  is  in  the 
general  direction  of  'the  route  to  be  mapped  and  the  com- 
pass to  the  right.  Hold  steadily  and  read  the  bearing. 
Unclamp  the  protractor  and  turn  it  until  the  index  on  the 
upper  plate  of  the  carrier  indicates  the  same  reading  on  the 
protractor  that  is  shown  by  the  needle.  The  instrument  is 
now  set,  and,  if  the  ruler  be  turned  to  zero,  it  will  lie  in  the 
magnetic  meridian. 

TO  PLACE  THE  CENTER  OF  THE  PROTRACTOR 
AND  THE  ZERO  OF  THE  SCALES  OVER 
ANY  POINT  ON  THE  PAPER. 

Move  the  paper  by  turning  one  of  the  rollers  until  the 
point  is  opposite  the  center  of  the  protractor.  Unclamp 
the  carrier  of  the  protractor  and  slide  it  along  the  bar  until 
the  center  of  the  protractor  is  over  the  point. 

SCALES. 

The  alidade  carries  two  scales.  The  one  on  the  right 
of  the  slit,  when  the  clamping  arm  is  to  the  right,  is  six 
inches  to  one  mile  ; the  one  on  the  left,  eight  inches  to  one 
mile  ; each  reading  to  twelve  and  one-half  yards.  Should 
it  be  desired  to  use  a scale  of  three  inches  to  one  mile,  or 
four  inches  to  one  mile,  use  the  six-inch  or  eight-inch  scale 
respectively,  giving  the  smallest  reading  a value  of  twenty- 
five  yards.  In  the  same  way  a scale  of  one  and  one-half 
inches  to  one  mile,  or  two  inches  to  one  mile,  may  be  ob- 
tained, the  smallest  reading  being  fifty  yards.  If  the  dis- 
tance is  measured  by  counting  paces,  find,  by  pacing  over  a 


208 


BATSON  SKETCHING-CASE. 


measured  distance,  the  number  of  steps  or  alternate  steps, 
taken  in  one  hundred  yards  ; then,  for  each  time  this  num- 
ber of  steps  is  counted,  score  one  hundred  yards.  The  total 
score  will  then  be  in  yards,  and  is  marked  off  on  the  scale 
of  yards.  This  method  will  be  found  to  cause  no  confu- 
sion. The  soldier  is  trained  to  estimate  distances  in  yards, 
and,  as  a great  deal  of  estimating  of  distances  is  required  in 
topographical  work,  a greater  degree  of  accuracy  can  be 
obtained  if  only  a scale  of  yards  is  used,  than  if  a scale  of 
steps  is  used  when  the  distance  is  paced,  and  a scale  of 
yards  when  the  distances  are  estimated.  The  latter  method 
is  also  open  to  the  objection  that  two  scales  must  be  pre- 
pared before  commencing  the  work.  Few  non-commis- 
sioned officers  and  privates  understand  scales  sufficiently 
well  to  construct  one,  although  but  little  explanation  is 
necessary  to  enable  them  to  use  one  already  constructed. 

For  keeping  tally,  a “ tally-register  ” is  most  conveni- 
ent, but  any  small  pasteboard  counter  will  answer. 


TO  USE  THE  SKETCHING-CASE . 

I.  As  a Plane-Table  : Set  the  instrument  as  explained. 
Select  a point  on  the  paper  for  the  initial  station.  This 
point  should  ordinarily  be  about  midway  of  the  edges  of 
the  paper  ; but  when  it  is  known  that  the  route  to  be  trav- 
eled deviates  considerably  to  one  side  or  the  other  from  the 
general  direction,  then  the  point  should  be  selected  on  the 
opposite  side  of  the  paper.  The  instrument  should  be  always 
so  set  and  the  point  representing  the  initial  station  so  se- 
lected, that  as  much  of  the  map  as  possible  may  be  sketched 
without  running  off  the  paper.  Having  selected  the  point 
representing  the  first  station,  center  the  protractor  over  this 
point.  Now,  holding  the  instrument  in  the  left  hand,  or 


BATSON  SKETCHING-CASE, 


209 


having  it  mounted  on  the  staff,  orient  it  until  the  reading  » 
of  the  needle  corresponds  to  the  reading  of  the  protractor 
circle.  Holding  it  steady  in  this  position,  turn  the  alidade 
upon  all  objects  it  is  desired  to  plot  on  the  map,  and  draw 
light  lines  in  the  slit  from  the  station-point  toward  them. 
These  objects  should  include  the  next  station  to  be  occu- 
pied. After  having  taken  the  slopes  in  the  vicinity  and 
sketched  in  the  detail,  the  ruler  is  clamped  in  the  direction 
of  the  next  station. 

II.  By  Plotting  the  Compass  Readings : With  the  pro- 

tractor set  as  explained  in  a previous  paragraph,  orient  the 
instrument  until  the  right-hand  edge  of  the  board  is  in  line 
with  the  object  to  be  plotted  upon  the  map,  and  then  read 
the  Compass.  Now,  turn  the  ruler  .to  the  corresponding 
reading  on  the  protractor  circle. 

Bearings  taken  with  the  Box  or  Prismatic  Compass  may 
be  plotted  upon  the  map  in  the  same  manner. 


PRICES. 

Batson  Sketching- Case,  as  shown  and  with  leather  case $30.00 

Wooden  Staff,  about  2 feet  long,  with  steel -pointed  shoe 1.00 

Plain  Tripod,  about  3^  feet  long 3.50 


THE  CURRENT-METER. 


FTER  six  years’  experience  in  measuring  the  velocity 


of  water  in  the  Ohio  and  Mississippi  rivers  by  differ- 
ent methods,  W.  G.  Price,  then  a U.  S.  Assistant  Engineer, 
devised  the  Current-Meter  known  by  his  name,  and  shown 
herewith.  It  is  used  by  the  U.  S.  Engineer  Corps,  the 
U.  S.  Coast  and  Geodetic  Survey,  and  by  Hydraulic  Engi- 
neers in  different  parts  of  the  country. 


wheel,  buckets,  as  shown,  so  arranged  as  to  feel  the 
force  of  the  slightest  current  and  cause  the  wheel  to  revolve. 

The  ends  of  the  axis  of  the  wheel  revolve  in  bearings 
contained  in  air-chambers  of  metal,  which  protect  them 
from  the  water  and  any  gritty  matter  it^  may  contain,  and 
the  friction  is  thus  reduced  to  a minimum  and  made  a 
constant  quantity.  The  form  of  the  wheel  and  buckets  is 
such  as  to  insure  great  strength  and  thus  resist  injury  from 
driftwood,  while  at  the  same  time  it  is  not  liable  to  obstruc- 
tion from  floating  leaves  and  grass. 

axis.  The  ax^s  the  wheel,  at  the  upper  end,  ex- 
tends above  its  bearing,  entering  an  air-tight  metal 
box  hereafter  named,  and  is  cut  down  f^r  a short  distance, 
forming  an  eccentric. 

A light  spring,  so  arranged  that  it  comes  in  contact  with 
the  eccentric,  bears  upon  this  divided  part  of  the  axis  and 
successively  makes  and  breaks  the  electric  circuit  as  the 
wheel  revolves. 

The  spring  and  divided  axis  form  the  contact-breaker, 
and  are  both  contained  in  the  little  meta)  air-tight  box 
which  is  shown  in  the  cut. 


BUCKET- 


The  wheel  of  this  Meter  carries  five  conical 


211 


212 


CURRENT -METERS. 


LEAD  WEIGHT 
AND  ROD. 


NO.  606.  B 


CURRENT-METERS. 


213 


A hollow  cylinder  of  bronze,  called  the  trunnion,  fitting 
easily  upon  the  rod,  supports  the  frame  of  the  Meter  by 
a pivot  on  each  side,  and  thus  by  the  rod 
trunnion.  ancj  pivots  the  Meter  is  free  to  move  both 

horizontally  and  vertically,  and  so  adjust  itself  to  the 
direction  of  the  current. 

The  frame  of  the  Meter  is  made  of  bronze,  and  is  very 
solid  and  strong.  The  rudder  has  four  light  metal  wings 
frame  and  or  vanes>  secured  to  a central  rod,  and  is 
rudder,  made  to  balance  the  weight  of  the  wheel  and 
give  direction  to  it,  and  thus  keep  the  wheel  in  both  direc- 
tions in  line  with  the  current.  The  Meter-frame  has  a 
hinged  side  secured  by  a spring  key,  allowing  the  Meter  and 
trunnion,  which  is  itself  in  two  parts,  to  be  detached  from 
the  rod  when  desired.  In  the  older  form  the  trunnion  was 
left  on  the  rod.  The  connecting  wires  are  passed  upward 
through  the  trunnion  of  the  Meter,  and  so  have  no  tendency 
to  pull  the  Meter  out  of  the  line  of  the  current. 

The  rod  is  of  brass  three-quarters  of  an  inch  in  diam- 
eter and  two  feet  long,  its  upper  end  having  an  eye  of 
brass  screwed  firmly  on  and  pinned,  and  its  lower  end 
screwed  into  a brass  socket  in  the  lead  weight,  B,  and 
secured  thereto  by  a jam-nut.  A sliding  ring  of  metal 
with  set-screw,  as  shown,  allows  the  Meter  to  be  raised  to 
any  point  on  the  rod. 

The  weight,  No.  606,  is  of  lead  and  weighs  about  sixty 
pounds  ; it  has  a rudder  of  wood,  as  shown, 
lead  weight.  secureci  to  the  weight  by  brass  cheek- 

pieces,  which  are  also  securely  fastened  to  the  weight  by 
sockets  cast  into  the  lead.  The  rudder  can  be  set  at  an 
angle  with  the  weight,  or  turned  up  parallel  with  the  rod, 
for  convenience  in  transportation. 

The  weight,  B,  is  only  used  where  the  Meter  is  em- 


214 


CURRENT-METERS. 


ployed  in  deep  water  and  harbor  surveying,  where  the 
currents  are  very  strong.  In  shallower  waters  the  Meter  is 
suspended  upon  a brass  rod.  These  rods  are  each  four  feet 
long  and  can  be  screwed  together  when  a long  length  is 
needed.  They  are  graduated  to  feet  and  tenths. 

SIZE  OF  THE  METER. 

We  now  make  but  one  size  of  this  Meter,  having  a 
wheel  six  inches  in  diameter,  and  the  total  length,  includ- 
ing the  rudder-van,  is  about  twenty-four  and  one-half 
inches  long.  This  Meter  is  adapted  for  deep  water  and 
harbor  surveying,  and  also  for  use  in  smaller  rivers  and 
streams,  and  is  used  either  with  or  without  the  weight. 

RATING  THE  METER. 

Before  using  the  Meter  it  is  necessary  to  obtain  its  rat- 
ing, which  is  the  number  of  revolutions  of  its  wheel  made 
in  passing  over  a measured  distance,  at  different  velocities. 

The  Meter  should  be  rated  in  still  water  which  is  not  less 

* 

than  five  feet  deep,  and  to  secure  a good  rating  there 
should  be  but  little  wind. 

It  should  be  attached  to  the  bow  of  a skiff,  as  shown  in 
the  cut,  and  immersed  not  less  than  two  feet.  The  boat 
should  have  no  rudder.  The  observer  should  also  stake  out 
two  parallel  range  lines  on  shore,  about  two  hundred  feet 
apart  and  at  right  angles  with  the  course  the  boat  is  to  take. 

Attach  a quarter-inch  cotton  cord  about  three  hundred 
feet  long  to  the  bow  of  the  boat,  and  pass  it  around  a 
pulley  which  is  placed  in  line  with  the  course  ; if  there  is  a 
bend  in  the  shore  the  pulley  may  not  be  necessary. 

It  will  require  three  or  four  men  to  pull  the  boat  fast 
enough  for  the  high  velocities,  and  there  must  be  a boatman 
with  oars  in  the  boat  with  the  observer,  to  prevent  its  run- 
ning into  the  shore. 


CURRENT-METERS. 


215 


Haul  the  boat  over  the  measured  base  at  very  slow, 
very  fast  and  medium  velocities,  which  should  be  as  nearly 
uniform  as  possible  during  each  passage. 

Note  before  each  trial  if  the  Meter  is  free  to  point  in 
the  direction  of  the  current,  as  the  connecting  wires  are 


liable,  in  backing  over  the  course,  to  get  twisted  so  as  to 
pull  the  Meter  out  of  line. 

Fasten  a vertical  rod  on  the  boat  near  the  seat  of  the 
observer,  to  enable  him  to  sight  at  the  range  stakes  as  he 
passes  them  ; start  the  Time-Recorder  (No.  619  of  Price- 
List)  and  Electric  Register  on  the  first  range-line  and  stop 
them  on  the  second  ; and  note  accurately  the  time  as  given 
by  the  Time-Recorder,  and  the  number  of  revolutions  of 
the  wheel  as  indicated  by  the  Register. 

The  rating  of  a Meter  (which  is,  in  brief,  the  value  in 
feet  per  second  of  one  revolution  of  the  wheel)  will  not 
change  as  long  as  the  wheel  turns  freely  and  has  not  been 
seriously  injured. 

The  velocity  of  a current  of  water  can  readily  be  computed 
from  the  Reduction-Table  furnished  with  the  instrument, 
and  also  given  on  pages  217  and  218,  the  number  of  revo- 
lutions of  the  wheel  per  second  having  been  already  ascer- 
tained by  observation,  and  recorded  by  the  Register. 

Should  the  observer  require  greater  accuracy,  it  is  ad- 
visable that  the  individual  rating  of  each  Meter  be  ob- 


216 


ELECTRIC  REGISTER  AND  BATTERY. 


tained.  If  desired,  we  will  rate  the  Meter,  furnishing  table 
at  a cost  of  from  twelve  to  fifteen  dollars. 

ELECTRIC  REGISTER . 

The  number  of  revolutions  of  the  Meter-wheel  is  re- 
corded by  an  Electric  Register  (shown  as  No.  609)  actuated 
by  a battery  of  three  cells. 

The  electric  current  proceeding  from  one  pole  of  the 
battery  is  carried  by  an  insulated  copper  wire  down  through 
the  trunnion  of  the  Meter,  and  thence  up  ta  the  insulated 
binding-post  on  the  upper  arm,  as  shown  in  the  cut ; thence 
through  the  contact-breaker,  the  axis  of  the  wheel,  and 
the  lower  arm,  to  the  binding-screw  shown  on  that  arm  ; 
thence  by  a second  copper  wire  up  through  the  trunnion  to 
one  binding-screw  of  the  Register  ; thence  through  the 
Register  to  the  other  binding-post  ; and  thence,  finally,  by 
another  wire  to  the  other  pole  of  the  battery. 

The  Electric  Register  is  enclosed  in  a brass  case,  show- 
ing three  dials  under  a glass  face,  and  has  an  electro- 
magnet which,  when  the  circuit  is  made,  moves  a lever,  at 
the  end  of  which  is  a pawl  carrying  forward  a ratchet-wheel 
one  tooth  at  every  contact  of  the  current.  The  large  dial  is 
graduated  into  one  hundred  spaces  and  two  small  dials  into 
ten  spaces  each,  all  reading  from  left  to  right.  The  large  dial 
counts  each  revolution  up  to  one  hundred, — the  small  dial 
on  the  right  counts  one  thousand  revolutions  by  each  hun- 
dred,— and  the  small  dial  on  the  left  counts  ten  thousand 
revolutions  by  each  thousand, — all  indicated  by  the  figuring. 

We  furnish  either  a dry-cell  or  wet-cell  battery,  as  may 
be  preferred,  to  operate  the  Electric  Register. 
Each  battery  is  composed  of  three  cells  en- 
closed in  a neat  wooden  case,  with  lock  and  strap. 

See  Nos.  610  and  612  of  the  Price-List. 


CURRENT-ME  TERS. 


217 


REDUCTION-TABLE  FOR  USE  WITH 
PRICE’S  PATENT  CURRENT-METER,  No.  600, 

WITH  6-INCH  * WHEEL. 

This  Table  is  a mean  of  several  ratings,  and  will  prob- 
ably give  correct  velocities  within  one  per  cent,  for  any 
Meter  when  in  good  order. 

Measurements  and  computations  by  W.  G.  Price, 
formerly  United  States  Assistant  Engineer. 


Rev. 
Per  Sec. 

Vel. 
Per  Sec. 

Rev. 
Per  Sec. 

Vel. 
Per  Sec. 

Rev. 
Per  Sec. 

Vel. 
Per  Sec. 

Rev. 
Per  Sec. 

Vel. 
Per  Sec. 

0.00 

0.145 

0.39 

1.372 

0.78 

2.584 

1.17 

3.766 

0.01 

0.176 

0.40 

1,404 

0.79 

2.614 

1.18 

3.796 

0.02 

0.208 

0.41 

1.435 

0.80 

2.645 

1.19 

3.826 

0.03 

0.239 

0.42 

1.467 

0.81 

2.676 

1.20 

3.856 

0.04 

0.271 

0.43 

1.498 

0.82 

2.706 

1.21 

3.886 

0.05 

0.302 

0.44 

1.529 

0.83 

2.737 

1.22 

3.916 

0.06 

0.334 

0.45 

1.560 

0.84 

2.767 

1.23 

3.945 

0.07 

0.365 

0.46 

1.592 

0.85 

2.798 

1.24 

3.975 

0.08 

0.397 

0.47 

1.623 

0.86 

2.829 

1.25 

4.005 

0.09 

0.428 

0.48 

1.654 

0.87 

2.859 

1.26 

4.035 

0.10 

0.460 

0.49 

1.686 

0.88 

2.890 

1.27 

4.065 

0.11 

0.491 

0.50 

1.717 

0.89 

2.920 

1.28 

4.094 

0.12 

0.523 

0.51 

1.748 

0.90 

2.951 

1.29 

4.124 

0.13 

0.554 

0.52 

1.779 

0.91 

2.981 

1.30 

4.154 

0.14 

0.586 

0.53 

1.811 

0.92 

3.012 

1.31 

4.183 

0.15 

0.617 

0.54 

1.842 

0.93 

3.042 

1.32 

4.213 

0.16 

0.649 

0.55 

1.873 

0.94 

3.073 

1.33 

4.242 

0.17 

0.680 

0.56 

1.904 

0.95 

3.103 

1.34 

4.272 

0.18 

0.712 

0.57 

1.935 

0.96 

3.133 

1.35 

4.301 

0.19 

0.743 

0.58 

1.967 

0.97 

3.164 

1.36 

4.331 

0.20 

0.775 

0.59 

1.998 

0.98 

3.194 

1.37 

4.360 

0.21 

0.806 

0.60 

2.029 

0.99 

3.225 

1.38 

4.390 

0.22 

0.838 

0.61 

2.060 

1.00 

3.255 

1.39 

4.419 

0.23 

0.869 

0.62 

2.091 

1.01 

3.285 

1.40 

4.449 

0.24 

0.901 

0.63 

2.122 

1.02 

3.315 

1.41 

4.478 

0.25 

0.932 

0.64 

2.153 

1.03 

3.345 

1.42 

4.508 

0.26 

0.963 

0.65 

2.183 

1.04 

3.375 

1.43 

4.537 

0.27 

0.995 

0.66 

2.214 

1.05 

3.405 

1.44 

4.566 

0.28 

1.026 

0.67 

2.245 

1.06 

3.436 

1.45 

4.595 

0.29 

1.058 

0.68 

2.276 

1.07 

3.466 

1.46 

4.624 

0.30 

1.089 

0.69 

2.307 

1.08 

3.496 

1.47 

4.654 

0.31 

1.120 

0.70 

2.338 

1.09 

3.526 

1.48 

4.683 

0.32 

1.152 

0.71 

2.369 

1.10 

3.556 

1.49 

4.713 

0.33 

1.183 

0.72 

2.399 

1.11 

3.586 

1.50 

4.742 

0.34 

1.215 

0.73 

2.430 

1.12 

3.616 

1.51 

4.771 

0.35 

1.246 

0.74 

2.461 

1.13 

3.646 

L52 

4.800 

0.36 

1.278 

0.75 

2.491 

1.14 

3.676 

1.53 

4.829 

0.37 

1.309 

0.76 

2.522 

1.15 

3.706 

1.54 

4.858 

0.38 

1.341 

0.77 

2.553 

1.16 

3.736 

1.55 

4.887 

VELOCITIES  ARE  IN  FEET  PER  SECOND. 


218 


CURRENT-ME  TERS . 


REDUCTION-TABLE.—  Continued . 


Rev. 
Per  Sec. 

Vel. 
Per  Sec. 

Rev. 
Per  Sec. 

Vel. 
Per  Sec. 

Rev. 
Per  Sec. 

Vel. 
Per  Sec. 

i 

Rev. 
Per  Sec. 

Vel. 
Per  Sec. 

1.56 

4.917 

1 

1.85 

5.755 

2.14 

6.584 

2.43 

7.400 

1.57 

4.946 

1.86 

5.784 

2.15 

6.612 

2.44 

7.428 

1.58 

4.975 

1.87 

5.813 

2.16 

6.640 

2.45 

7.456 

1.59 

5.004 

1.88 

5.842 

2.17 

6.669 

2.46 

7.484 

1.60 

5.033 

1.89 

5.870 

2.18 

6.697 

2.47 

7.512 

1.61 

5.062 

1.90 

5.899 

2.19 

6.726 

2.48 

7.540 

1.62 

5.091 

1.91 

5.928 

2.20 

6.754 

2.49 

7.568 

1.63 

5 120 

1.92 

5.956 

2.21 

6.782 

2.50 

7.596 

1.64 

5.149 

1.93 

5.985 

2.22 

6.810 

2.51 

7.624 

1.65 

5.178 

1.94 

6.013 

2 23 

6.838 

2.52 

7.652 

1.66 

5.207 

1.95 

6.042 

2.24 

6.866 

2.53 

7.680 

1.67 

5.236 

1.96 

6.071 

2,25 

6.894 

2.54 

7.708 

1.68 

5.265 

1.97 

6.099 

2.26 

6.923 

2.55 

7.735 

1.69 

5.294 

1.98 

6.128 

2.27 

6.951 

2.56 

7.763 

1.70 

5.323 

1.99 

6.156 

2.28 

6.979 

2.57 

7 791 

1.71 

5.352 

2.00 

6.185 

2.29 

7.007 

2.58 

7.819 

1.72 

5.381 

2.01 

6.213 

2 30 

7.035 

2.59 

7 847 

1.73 

5.410 

2.02 

6.242 

2.31 

7.063 

2.60 

7.875 

1.74 

5.439 

2.03 

6.270 

2.32 

7.091 

2.61 

7.903 

1.75 

5.467 

2.04 

6.299 

2.33 

7.119 

2.62 

7.931 

1.76 

5.496 

2.05 

6.327 

2.34 

7.147 

2 63 

7.958 

1.77 

5.525 

2.06 

6.356 

2.35 

7 175 

2.64 

7.986 

1.78 

5.554 

2.07 

6.384 

2.36 

7.204 

2.65 

8 014 

1.79 

5.583 

2.08 

6.413 

2.37 

7.232 

2.66 

8.042 

1.80 

5.612 

2.09 

6. *441 

2.38 

7.260 

2.67 

8.070 

1.81 

5.641 

2.10 

6.470 

2.39 

7.288 

2.68 

8.097 

1.82 

5.669 

2.11 

6.498 

2.40 

7.316 

2.69 

8.125 

1.83 

5.698 

2.12 

6.527 

2.41 

7.344 

2.70 

8.153 

1.84 

5.727 

2.13 

6.555 

2.42 

7.372 

VELOCITIES  ARE  IN  FEET'  PER  SECOND. 


REDUCTION  -TABLE. 

To  be  used  in  reducing  observed  velocities  to  the  mean 
vertical  velocity.  The  mean  velocity  is  about  ninety-six 
per  cent,  of  the  mid-depth  velocity. 


Depth. 

Per  Cent. 

Depth  . 

Per  Cent. 

Depth. 

Per  Cent. 

A 

0.952 

4 

TO- 

0.958 

7 

T7F 

0.984 

A 

0.951 

5 

TF 

0.960 

8 

TTT 

1.020 

A 

0.948 

6 

TTT 

0.965 

9 

TF 

1.140 

MULTIPLY  THE  MEASURED  VELOCITY  BY  THE  PERCENTAGE. 


CURRENT-ME  TERS. 


219 


PRICKS  ACOUSTIC  CURRENT-METER. 

(PATENTED.) 

This  Meter  was  devised  by  W.  G.  Price,  and  has  many 
points  of  excellence.  It  is  very  compact,  light  and  portable, 
and  is  especially  designed  for  use  in  irrigation  ditches,  or 
streams  where  there  is  little  depth  of  water.  The  cut  shows 

I the  external  appearence  of  the 
Meter,  with  the  brass  tubes  by  which 
it  is  held  while  in  use.  The  revolu- 
tions of  the  wheel  are  indicated  by 
a hammer  striking  against  a dia- 
phragm, one  blow  for  every  ten  revo- 
lutions, and  the  recording  mechan- 
ism is  enclosed  in  the  stem  of  the 
Meter  and  thoroughly  protected 
from  injury.  The  sound  of  the 
recording  stroke  is  transmitted 
through  the  tubing  supporting  the 
Meter,  and  is  conveyed  to  the  ear 
of  the  operator  by  the  rubber  ear- 
tube.  In  use  the  operator  fixes  the 
ear-tube  in  position  by  a rubber 
band  passing  around  his  head,  and  thus  both  hands  are  left 
free  for  the  manipulation  of  the  Meter.  Results  obtained 
maybe  readily  reduced  by  the  use  of  the  Reduction-Table 
supplied  with  the  Meter,  and  also  given  on  pages  220  and  221. 

Each  Meter  is  packed  in  a wooden  box  with  lock  and 
strap,  and  is  provided  with  two  lengths  of  nickel-plated  brass 
tubing,  graduated  to  feet  and  tenths  up  to  four  feet,  and 
with  four  feet  of  rubber  tubing  with  all  necessary  connec- 
tions. Extra  graduated  brass  tubing,  in  lengths  of  two  feet, 
will  be  furnished  when  desired,  at  a cost  of  $2.50  per  length. 


NO.  616. 

Price,  $50.00. 


220 


CURRENT-ME  TERS. 


REDUCTION-TABLE  FOR  USE  WITH 

PRICE’S  PATENT  ACOUSTIC  CURRENT-METER. 

The  time  column  is  the  number  of  seconds  occupied  by 
one  hundred  revolutions  of  the  wheel,  there  being  ten 
revolutions  to  each  “ rap.” 

The  velocity  column  is  the  velocity  in  feet  per  second. 


Time. 

Velocity. 

■ 

, 

Time. 

Velocity. 

Time. 

Velocity. 

Time. 

Velocity. 

700 

0.377 

298 

0.843 

256 

0.981 

214 

1.166 

690 

0.383 

297 

0.846 

255 

0.985 

213 

1.170 

680 

0.389 

296 

0.849 

254 

0.988 

212 

1.176 

670 

0.394 

295 

0.853 

253 

0.991 

211 

1.183 

660 

0.400 

294 

0.856 

252 

0.995 

210 

1.189 

650 

0.406 

293 

0.860 

251 

1.000 

209 

1.195 

640 

0.413 

292 

0.863 

250 

1.004 

208 

1.199 

630 

0.419 

291 

0.866 

249 

1.008 

207 

1.204 

620 

0.426 

290 

0.868 

248 

1.012 

206 

1.208 

610 

0.432 

289 

0.871 

247 

1.016 

205 

1.214 

600 

0.439 

288 

0.874 

246 

1.019 

204 

1.220 

590 

0.447 

287 

0.877 

245 

1.023 

203 

1.226 

580 

0.454 

286 

0.879 

244 

1.027 

202 

1.233 

570 

0.462 

285 

0.882 

243 

1.032 

201 

1.239 

560 

0.469 

284 

0.886 

242 

1.036 

200 

1.247 

550 

0.477 

283 

0.889 

241 

1.040 

199 

1.253 

540 

0.485 

282 

0.893 

240 

1.044 

198 

1.258 

530 

0.493 

281 

0.896 

239 

1.048 

197 

1.263 

520 

0.502 

280 

0.899 

238 

1.052 

196 

1.270 

510 

0.511 

279 

0.902 

237 

1.056 

195 

1.277 

500 

0.520 

278 

0.905 

236 

1.060 

194 

1.284 

490 

0.529 

277 

0.908 

235 

1.064 

193 

1.291 

480 

0.538 

276 

0.911 

234 

1.067 

192 

1.297 

470 

0.546 

275 

0.914 

233 

1.071 

191 

1.303 

460 

0.555 

274 

0.917 

232 

1.076 

190 

1.310 

450 

0.569 

273 

0.920 

231 

1.082 

189 

1.316 

440 

0.583 

272 

0.924 

230 

1.087 

188 

1.322 

430 

0.597 

271 

0.928 

229 

1.092 

187 

1.328 

420 

0.610 

270 

0.932 

228 

1.097 

186 

1.335 

410 

0.624 

269 

0.936 

227 

1.102 

185 

1.342 

400 

0.637 

268 

0.939 

226 

1.106 

184 

1.349 

390 

0.653 

267 

0.942 

225 

1.111 

183 

1.357 

380 

0.668 

266 

0.944 

224 

1.116 

182 

1.363 

370 

0.684 

265 

0.947 

223 

1.121 

181 

1.370 

360 

0.705 

264 

0.951 

222 

1.126 

180 

1.377 

350 

0.726 

263 

0.955 

221 

1.131 

179 

1.385 

340 

0.747 

262 

0.959 

220 

1.136 

178 

1.393 

330 

0.768 

261 

0.963 

219 

1.142 

177 

1.401 

320 

0.789 

260 

0.967 

218 

1.147 

176 

1.408 

310 

0.813 

259 

0.971 

217 

1.152 

175 

1.416 

300 

0.837 

258 

0.974 

216 

1.15? 

174 

1.424 

299 

0.840 

257 

0.978 

215 

1.161 

173 

1.432 

CURRENT-METERS . 


221 


REDUCTION -TABLE.—  Continued . 


The  time  column  is  the  number  of  seconds  occupied  by 
one  hundred  revolutions  of  the  wheel,  there  being  ten 
revolutions  to  each  “ rap/' 

The  velocity  column  is  the  velocity  in  feet  per  second. 


Time. 

| 

Velocity. 

Time. 

Velocity. 

Time. 

Velocity. 

Time. 

Velocity. 

172 

1.439 

133 

1.847 

94 

2.600 

55 

4.399 

171 

1.446 

132 

1.859 

93 

2.629 

54 

4.477 

170 

1.453 

131 

1.873 

92 

2.657 

53 

4.560 

169 

1.461 

130 

1.887 

91 

2.686 

52 

4.647 

168 

1.469 

129 

1.901 

90 

2.714 

51 

4.737 

167 

1.477 

128 

1.917 

89 

2.742 

50 

4.830 

166 

1.485 

127 

1.932 

88 

2.770 

49 

4.926 

165 

1.494 

126 

1.947 

87 

2.800 

48 

5.026 

164 

1.502 

125 

1.962 

86 

2.834 

47 

5.132 

163 

, 1.510 

124 

1.977 

85 

2.867 

46 

5.242 

162 

' 1.521 

123 

1.992 

84 

2.902 

45 

5.354 

161 

1.532 

122 

2.008 

83 

2.938 

44 

5.473 

160 

1.544 

121 

2.023 

82 

2.973 

43 

5.598 

159 

1.553 

120 

2.040 

81 

3.008 

42 

5.730 

158 

1.560 

119 

2.058 

80 

3.044 

41 

5.866 

157 

1.570 

118 

2.077 

79 

3.083 

40 

6.011 

156 

1.580 

117 

2.096 

78 

3.123 

39 

6.161 

155 

1.592 

116 

2.115 

' 77 

3.164 

38 

6.323 

154 

1.602 

115 

2.133 

76 

3.205 

37 

6.492 

153 

1.614 

114 

2.150 

75 

3.246 

36 

6.667 

152 

1.623 

113 

2.168 

74 

3.289 

35 

6.854 

151 

1.631 

112 

2.186 

73 

3.334 

34 

7.051 

150 

1.641 

111 

2.204 

72 

3.379 

33 

7.265 

149 

1.652 

110 

2.223 

71 

3.425 

32 

7.490 

148 

1.664 

109 

2.243 

70 

3.473 

31 

7.730 

147 

1.675 

108 

2.264 

69 

3.520 

30 

7.981 

146 

1.686 

107 

2.285 

68 

3.568 

29 

8.259 

145 

1.698 

106 

2.306 

67 

3.618 

28 

8.550 

144 

1.710 

105 

2.328 

66 

3.674 

27 

8.860 

143 

1.721 

104 

2.349 

65 

3.731 

26 

9.194 

142 

1.732 

103 

2.372 

64 

3.789 

25 

9.560 

141 

1.743 

102 

2.395 

63 

3.848 

24 

9.954 

140 

1.755 

101 

2.418 

62 

3.909 

23 

10.372 

139 

1.767 

100 

2.442 

61 

3.972 

22 

10.835 

138 

1.779 

99 

2.466 

60 

4.035 

21 

11.347 

137 

1.792 

98 

2.492 

59 

4.103 

20 

11.907 

136 

1.806 

97 

2.518 

58 

4.173 

135 

1.819 

96 

2.545 

57 

4.245 

134 

1.834 

95 

2.572 

56 

4.322 

222 


CURRENT-ME  TERS. 


ELECTRIC  CURRENT-METER. 

FOR  USE  IN  SMALL  STREAMS. 


No.  617. 


Price,  as  shown,  $70.00. 

The  importance  of  correct  hydraulic  measurements  has 
brought  the  Current-Meter  into  general  use,  and  while  the 
Price-Current-Meter,  No.  600,  has  long  been  recognized 
as  standard  for  observation  on  large  streams,  in  recent 
years  there  has  been  a demand  for  a light  and  serviceable 
instrument  for  use  in  small  streams  and  irrigation  or  drain- 
age ditches. 

In  response  to  this  demand,  the  Acoustic  Current-Meter, 
indicating  by  sound  the  revolutions  of  the  wheel,  was  intro- 


CURRENT-METERS. 


223 


duced,  and  this  instrument  has  met  with  a favorable  recep- 
tion by  hydraulic  engineers. 

Many  observers,  however,  prefer  that  the  revolutions  of 
tne  wheel  should  be  indicated  by  the  making  and  breaking 
of  an  electric  current. 

For  some  time,  aided  by  the  suggestions  of  the  engineers 
in  charge  of  the  hydrographic  work  of  the  United  States 
Geological  Survey,  we  have  been  perfecting  the  small 
Electric  Current-Meter  shown  in  the  cut,  and  listed  in  our 
catalogue  as  No.  617.  This  Meter,  while  constructed  prac- 
tically along  the  lines  of  Current-Meter  No.  600,  has  the 
advantage  of  Extreme  lightness,  weighing  only  about  two 
pounds. 

The  electrical  connection  is  made  in  the  same  manner 
as  is  described  under  Meter  No.  600.  The  Meter  is  sup- 
ported in  a trunnion,  and  is  free  to  swing  in  a vertical  plane. 
The  vane  is  so  made  that,  if  desired,  it  may  be  taken  apart 
for  convenience  in  transportation. 

In  use,  the  Meter  is  suspended  by  a cable  containing 
the  wires  for  electrical  connection,  and  is  held  steady  by  a 
lead  weight,  as  shown  in  the  cut. 

The  electric  sounder  is  very  simple,  consisting  of  a 
“ buzzer  ” attached  to  a small  leather  case  containing  a bi- 
sulphate of  mercury  battery  cell. 

Each  revolution  of  the  wheel  is  indicated  by  a “ buzz,” 
the  observer  being  required  to  count  the  number  in  a cer- 
tain period  of  time. 

The  Meter  is  packed  in  a wooden  box,  strongly  made, 
and  of  a capacity  sufficient  to  contain  the  Meter,  lead 
weight,  sounder,  wire  and  other  apparatus  for  the  observer. 

A table  for  reducing  observations  has  been  prepared 
which  will  give  correct  values  within  one  per  cent. 

Should  the  observer  require  greater  accuracy,  it  is  ad- 


224 


CURRENT-ME  TERS. 


visable  that  the  individual  rating  of  each  Meter  be  ob- 
tained. If  desired,  we  will  rate  the  Meter,  furnishing  table 
at  a cost  of  from  twelve  to  fifteen  dollars. 


The  price  of  the  Meter  is  $60.00 

The  price  of  the  lead  weight  is 2.50 

The  price  of  the  sounder  is 7. 50 

The  price  of  the  Meter,  including  lead  weight  and  sounder  and 

twenty  feet  of  cable,  is  70.00 

Extra  length  of  cable,  10  cents  per  foot. 


Reduction  Table  for  use  with  Electric  Current- Meter 
No.  617.  This  Table  is  a mean  of  the  ratings  of  ten  sepa- 
rate Meters  and  will  probably  give  correct  values  within 
one  per  cent,  of  any  Meter  of  its  pattern  in  good  order. 


Rev.  | 
Per  Sec. 

Vel. 
Per  Sec. 

Rev. 
Per  Sec. 

Vel. 

'Per  Sec. 

Rev. 
Per  Sec. 

Vel. 
Per  Sec. 

Rev. 
Per  Sec. 

Vel.  ! 
Per  Sec. 

0.00 

.10 

1.00 

2.38 

2.00 

4.73 

3.00 

7.08 

0.05 

.21 

1.05 

2.50 

2.05 

4.85 

3.05 

7.20 

0.10 

.32 

1.10 

2.62 

2.10 

4.97 

3.10 

7.32 

0.15 

.43 

1.15 

2 74 

2.15 

5.08 

3.15 

7.44 

0.20 

.55 

1.20 

2.86 

2.20 

5.20 

3.20 

7.55 

0.25 

.66 

1.25 

2.97 

2.25 

5.32 

3.25 

7.67 

0.30 

.77 

1.30 

3.09 

2.30 

5.44 

3.30 

7.79  • 

0.35 

.88 

1.35 

3.20 

2.35 

5.56 

3.35 

7.91 

0.40 

1.00 

1.40 

3.32 

2.40 

5.67 

3.40 

8.02 

0.45 

1.11 

1.45 

3.44 

2.45 

5.79 

3.45 

8.14  ; 

0.50 

1.23 

1.50 

3.56 

2.50 

5.90 

3.50 

8.26 

0.55 

1.34 

1.55 

3.67 

2.55 

6.02 

3. DO 

8.37 

0.60 

1.46 

1.60 

3.79 

2.60 

6.14 

3.60 

8.49 

0.65 

1.58 

1.65 

3.91 

2.65 

6.26 

3.65 

8.61 

0.70 

1.69 

1.70 

4.03 

2.70 

6.38 

3.70 

8.73 

0.75 

1.81 

1.75 

4.14 

2.75 

6.50 

3.75 

8.84 

0.80 

1.92 

1.80 

4.26 

2.80 

6.61 

3.80 

8.95 

0.85 

2.04 

1.85 

4.38 

2.85 

6.73 

3.85 

9.07 

0.90 

2.15 

1.90 

4.50 

2.90 

6.84 

3.90 

9.19 

0.95 

1 

2.27 

1.95 

4.61 

2.95 

6.96 

3.95 

4.00 

9.31 

9.43 

BOYDEN'S  HOOK- GAUGE. 


225 


NO.  620. 

Price,  $25.00. 


BOYDENyS  HOOK -GAUGE, 

So  called  from  the  name  of  its  inventor,  is  used 
in  determining  the  depth  of  water  flowing  over 
weirs,  etc. 

As  represented  in  the  cut,  it  has  a frame  of 
wood,  three  feet  long  and  four  inches  wide,  in 
a rectangular  groove  of  which  another  piece  is 
made  to  slide,  carrying  a metallic  scale  divided 
to  feet  and  hundredths,  and  figured  from  zero 
to  two  feet  and  two-tenths,  as  shown. 

Connected  with  the  scale  is  a brass  screw 
passing  through  a socket,  fastened  to  another 
shorter  sliding  piece,  shown  above,  which  can 
be  clamped,  at  any  point  on  the  frame,  and  the 
scale  with  hook  moved  in  either  direction  by 
the  milled  head  nut. 

There  is  also  a vernier  attached  to  the  frame, 

and  movable  under  the  screw  heads  which  se- 

« 

cure  it,  in  order  to  adjust  its  zero  to  correspond 
with  the  point  of  the  hook,  as  will  be  described 
hereafter.  The  vernier  reads  the  scale  to  thou- 
sandths of  a foot. 

The  hook  is  of  brass,  and  has  a sharp  point 
which,  when  raised  to  the  surface  of  the  water1 
at  rest,  indicates  its  precise  level. 

TO  USE  THE  HOOK-GAUGE. 


The  hook-gauge  is  used  in  a box  attached  to  a flume  at 
any  convenient  point  near  the  weir,  the  water  in  the  flume 
being  conveyed  to  the  box  by  rubber  or  lead  pipes,  and  thus 
indicating  the  precise  level  of  the  water  in  the  flume,  the 
surface  of  the  water  in  the  box  being  also  at  rest. 


226 


BOYDEN'S  HOOK-GAUGE. 


When  the  depth  of  the  water  passing  over  a weir  is  re- 
quired, the  exact  level  of  the  crest  of  the  weir  should  be 
taken  by  a leveling-instrument  and  rod,  and  designated  by 
a line  drawn  in  the  still-water  box  above  the  surface  of  the 
water.  The  scale  of  the  gauge  being  previously  set  at 
zero  with  the  vernier,  the  frame  is  fastened  to  the  box 
above  the  water  in  such  a position  that  the  point  of  the  hook 
is  at  the  same  level  with  that  of  the  crefet  of  the  weir,  the 
precise  point  being  secured  by  the  adjusting-screw  of  the 
scale.  Now  see  that  the  zeros  of  the  scale  and  vernier  are 
in  line,  and  if  not,  move  the  vernier  under  the  screw  heads 
until  the  zeros  correspond,  and  set  the  vernier  fast.  The 
point  of  the  hook  will,  of  course,  be  under  water,  and  at  the 
same  time  level  with  that  of  the  crest  of  the  weir. 

The  depth  of  the  water  flowing  over  the  weir  is  the  dis- 
tance between  the  point  of  the  hook  in  the  position  named 
and  the  exact  surface  of  the  water.  To  find  this,  the  hook 
is  raised  by  turning  the  milled  head  nut  until  the  point  of 
the  hook,  appearing  a little  above  the  surface,  causes  a 
distortion  in  the  reflection  of  the  light  from  the  surface  of 
the  water  ; then  a little  movement  of  the  hook  in  the  oppo- 
site direction  will  cause  the  distortion  to  disappear,  and 
will  indicate  the  surface  with  precision.  The  reading  of 
the  scale  will  then  give  the  depth  of  water  passing  over 
the  weir,  in  thousandths  of  a foot. 

It  will  be  understood  from  the  cut  that  the  longer  move- 
ments of  the  scale  are  made  by  moving  the  clamping  piece 
over  the  frame,  the  smaller  adjustments  being  effected  by 
the  milled  nut. 

Note.- — We  also  make  to  order,  from  designs  furnished,  Water- Regis- 
ters, Tide-Gauges  and  similar  instruments. 


V 


228 


BAND-LEVELS. 


TELESCOPIC  BAND-LEVELS. 

(PATENTED.) 


NO.  625.  NO.  627. 

Price,  $12.00.  Price,  $15.00. 


The  figures  represent  instruments  devised  by  us  to 
remedy  the  defects  of  the  ordinary  Hand-Levels,  and  to  in- 
crease their  usefulness  in  the  work  of  the  engineer. 

The  Monocular  Hand-Level,  shown  as  No.  625,  consists 
of  a tube  to  which  are  fitted  the  lenses  of  a single  opera- 
glass,  containing  in  addition  a reflecting  prism,  cross-wire 
and  level-vial,  the  last  being  shown  in  the  open  part  of  the 
tube. 

The  eye-lens,  as  indicated  in  the  cut,  is  made  of  two 
separate  pieces,  the  larger  one  being  the  usual  concave  eye- 
lens  of  the  opera-glass  and  the  smaller  one  a segment  of  a 
plano-convex  lens,  having  its  focus  in  a cross-wire  under 
the  level-vial  and  above  the  reflecting  prism. 

The  observer  holds  the  tube  horizontal  with  the  level- 
opening uppermost,  and  observes  the  object  to  which  the 


HAND-LEVELS. 


229 


instrument  is  directed  and  the  position  of  the  level-bubble 
with  reference  to  the  cross-wire  on  the  under  side  of  the 
level-vial. 

When  the  Hand-Level  is  held  truly  horizontal  the  cross- 
wire will  bisect  the  bubble,  and  will  also  determine  the  level 
of  any  object  seen  through  the  telescope  ; thus  securing  to 
the  observer  a clear  view  of  the  object,  magnified  also  by 
the  telescope. 

The  Binocular  Hand-Level,  shown  as  No.  627,  consists 
of  two  tubes,  that  on  the  right  enclosing  the  usual  lenses 
of  the  opera-glass,  while  the  tube  on  the  left  contains  only 
the  prism,  level-vial  and  cross-wire  of  the  instrument  just 
described. 

This  Level  is  used  like  the  ordinary  opera-glass,  the  level- 
vial  being  above,  as  shown  in  the  cut. 

When  the  tubes  are  held  truly  horizontal,  the  engineer, 
with  one  eye,  will  see  the  cross-wire  bisecting  the  bubble, 
and,  with  the  other  eye,  the  object  observed,  the  level  line 
of  which  is  determined  by  the  position  of  the  cross-wire 
upon  its  surface. 

The  use  of  the  Binocular  Hand-Level  gives  a clearer 
view  of  an  object  than  is  possible  with  a single  tube,  there 
being  now  no  light  lost  by  the  interference  of  the  prism  and 
level-vial. 

The  Hand-Level  is  adjusted  by  sliding  the  prism-tube 
back  and  forth  until  the  line  given  is  the  same  as  that  given 
by  a Y-Level. 

The  prism  in  the  tube  can  be  reached  by  removing  the 
cap  from  the  closed  end  of  the  tube,  and  it  is  clamped  by  a 
small  screw  on  the  lower  side. 


230 


HAND-LEVELS. 


LOCKE'S  HAND-LEVEL. 


NO.  630. 

Price,  $8.00. 


This  instrument  consists  of  a brass  tube  about  six  inches 
long,  having,  as  shown  in  the  figure,  a level-vial  on  top  and 
near  the  object  end.  There  is  also  an  opening  in  the  tube 
beneath,  through  which  the  bubble  can  be  seen,  as  reflected 
by  a prism  immediately  under  the  level-vial.  Both  ends  of 
the  tube  are  closed  by  disks  of  plain  glass  to  exclude  the 
dust,  and  there  is  at  the  inner  end  of  the  sliding  or  eye-tube 
a semi-circular  convex  lens,  which  serves  to  magnify  the 
level-bubble  and  the  cross-wire  beneath,  while  it  allows  the 
object  to  be  clearly  seen  through  the  open  half  of  the  tube. 

The  cross-wire  is  fastened  to  a little  frame  moving  under 
the  level-tube  and  adjusted  to  its  place  by  the  small  screw 
shown  on  the  end  of  the  level-case.  The  level  of  any 
object  in  line  with  the  eye  of  the  observer  is  determined  by 
sighting  upon  it  through  the  tube,  and  bringing  the  bubble 
of  the  level  into  a position  where  it  is  bisected  by  the  cross- 


wire. 


HAND-LEVELS. 


231 


THE  ABNEY  LEVEL 
AND  CLINOMETER . 

NO.  634. 


The  Abney  Level  is  a modification  of  the  Locke’s 
Hand-Level,  combining  with  it  an  excellent  clinometer, 
as  shown  in  the  cut. 

The  main  tube  being  square,  it  can  be  applied  to  any 
surface,  the  inclination  of  which  is  ascertained  by  bringing 
the  level-bubble  into  the  middle  and  reading  off  the  angle 
by  the  vernier  and  arc  ; or  when  sighted  at  an  object  and 
the  bubble  brought  into  the  middle,  the  vertical  angle  from 
the  height  of  the  eye  is  indicated.  When  at  zero  it  would 
indicate  a level  line. 

The  inner  and  shorter  arc  indicates  the  lines  of  differ- 
ent degrees  of  slope,  the  left-hand  end  of  the  vernier  being 
applied  to  the  lines  and  the  bubble  being  brought  into  the 
middle,  as  usual.  A small  compass,  with  needle  about  one 
and  one-half  inches  long,  is  sometimes  attached  to  the  upper 
surface  of  the  Abney  Level,  with  a plain  staff  socket  below. 


PRICES. 

No.  Price.  Post. 

634.  Abney  Level,  an  improved  “ Locke’«  Hand-Level,” 
giving  angles  of  elevation,  and  is  also  divided  for 
slopes,  as  1 to  1,  2 to  1,  etc.;  in  case $>13.50  $0.25 

636.  Same  as  No.  634,  and  with  compass  and  plain  staff 

socket  attached 18.00  .30 


CHAINS. 


The  sizes  and  diameters  of  iron  and  steel  wire  com- 
monly used  in  making  surveyors’  and 
sizes  of  wire.  engineers’  chains  are  as  follows  : No. 

8,  .162-inch  ; No.  10,  .135-inch  ; No.  12,  .105-inch  ; No.  15, 
.072-inch  ; No.  18,  .047-inch. 

The  ordinary  Gunter’s  or  surveyors’  chain  is  sixty-six 
feet  or  four  poles  long,  composed  of  one  hundred  links, 
land  surveyors’  each  connected  to  the  other  by  two 
chains.  rings,  and  furnished  with  a tally- 

mark  at  the  end  of  every  ten  links.  A link  in  measurement 
includes  a ring  at  each  end,  and  is  seven  and  ninety-two 
one-hundredths  inches  long.  In  all  the  chains  we  manufac- 
ture the  rings  are  oval  and  are  sawed  and  well  closed,  the 
ends  of  the  wire  forming  the  hook  being  also  filed  and  bent 
close  to  the  link,  to  avoid  the  danger  of  kinking.  The 
oval  rings  are  about  one-third  stronger  than  round  ones. 

The  handles  are  of  brass  and  form  part  of  the  end 
links,  to  which  they  are  connected  by  a short 
handles.  anc[  jam-nuts,  by  which  also  the  length 

of  the  chain  is  adjusted. 

The  tallies  are  of  brass,  and  have  one,  two,  three  or  four 
notches,  as  they  mark  ten,  twenty,  thirty  or 
talli  es.  forty  links  from  either  end.  The  fiftieth  link  is 
marked  by  a rounded  tally  to  distinguish  it  from  the  others. 

In  place  of  the  four-pole  chain  just  described,  many 
surveyors  prefer  a chain  two  rods  or 
half-chains,  thirty-three  feet  long,  and  having  only 

fifty  links,  which  are  counted  by  tallies  from  one  end  in  a 
single  direction. 


233 


234 


CHAINS. 


Our  surveyors’  chains  are  made  of  Nos.  8 and  10  re- 

I RO  N AND  STEEL  fine<^  ^ron  wire>  anC*  °f  Nos.  8,  10,  12 
wire.  and  15  best  steel  wire.  Steel  chains, 

though  more  costly  than  those  of  iron,  are  often  preferred 
on  account  of  their  greater  strength. 

Engineers’  chains  differ  from  surveyors’  chains,  in  that 
engineers’  a including  a ring  at  each  end  is 

chains.  one  foot  long,  and  the  wire  is  of  steel  and 
therefore  much  stronger. 

They  are  either  fifty  or  one  hundred  feet  long,  and  are 
furnished  with  swivel  handles  and  tallies  like  those  just 
described. 

The  wire  used  for  these  chains  is  of  steel,  Nos.  8,  10 
and  12  of  the  first  quality. 

A very  light  and  strong  chain  is  made  of  No.  12  steel 
brazed  steel  wire>  the  links  and  rings  of  which  are 
chains.  securely  brazed.  The  wire  is  of  a low 
spring-temper,  and  the  chain  though  light,  is  almost  incap- 
able of  being  either  broken  or  stretched  in  ordinary  use. 

Our  brazed  steel  chains  have  been  found  exceedingly 
desirable  for  all  kinds  of  measurement,  and  for  the  use  of 
engineers  upon  railroads  and  canals  they  have  almost  en- 
tirely superseded  the  heavier  chains. 

We  often  make  chains  with  steel  snaps  in  the  middle 
and  at  one  handle.  The  chain  can  then  be  separated,  and 
one  handle  being  removed  and  transferred 
steel  snaps.  tQ  forty-ninth  link,  a chain  of  half 

length  is  obtained.  This  modification  is  made  without 
charge  if  ordered  with  the  chain. 

TO  USE  THE  CHAIN. 

In  using  the  chain  the  length  must  be  taken  from  the 
extreme  ends,  and  the  marking-pins  placed  on  the  outside 


CHAINS. 


235 


of  the  handles.  It  must  be  drawn  straight  and  taut,  and 
carefully  examined  to  detect  any  kinks  or  other  causes  of 
inaccuracy. 

standard  Our  chains  are  all  carefully  tested  at  every 
measure.  anc|  jn  their  whole  length,  by  the  U.  S. 

standard,  with  a strain  of  ten  pounds  and  with  temperature 
at  62°  Fahrenheit,  and  when  new  may  always  be  relied  upon 
as  correct. 

But  as  all  chains  will  be  lengthened  more  or  less  after 
long  use  in  the  field,  it  will  be  best  for  the  surveyor  to  ' 
carefully  lay  down  on  a level  surface  the  exact  length  of 
the  chain  when  new,  marking  its  extreme  ends  by  monu- 
ments which  will  not  be  liable  to  disturbance. 

He*  will  thus  have  a standard  measure  of  his  own  to 
which  the  chain  can  be  adjusted  from  time  to  time,  and 
again  be  used  with  perfect  confidence. 

GRUMMAN'S  PATENT  CHAINS . 

These  chains,  invented  and  patented  by  J.  M.  Grumman, 
of  Brooklyn,  N.  Y.,  are  made  of  very  light  steel  wire,  the 
links  being  finely  tempered,  and,  as  shown  in  the  cut,  so 
formed  at  the  ends  as  to  fold  together  readily,  and  thus 
dispense  with  the  use  of  rings. 


This  construction  gives  but  one-third  as  many  wearing 
points  as  on  the  ordinary  chain,  and  affords  the  utmost 
facility  for  repairs. 

Five  or  ten  extra  links  are  furnished  with  each  chain, 
and  these  have  only  to  be  sprung  into  place  to  replace 


236 


CHAIN’S. 


such  as  may  have  been  broken.  The  chain  can  also  be 
sprung  apart  at  any  link,  and  thus  be  made  of  any  length 
desired. 

Some  of  these  chains  are  made  of  No.  15  wire,  and 
are  used  for  measuring  on  the  surface  like  the  ordinary 
chain.  One  is  used  as  a suspended  chain,  for  very  accurate 
measurements,  and  is  made  of  No.  18  wire  and  provided 
with  spring-balance,  level  and  thermometer  attachments. 
It  is  held  above  the  surface  when  in  use,  and  the  extremi- 
ties of  the  chain  are  marked  upon  the  ground  by  the  points 
of  plummets  let  fall  from  fixed  places  on  the  chain. 

VARA  CHAINS. 

The  vara,  which  is  in  general  use  in  Texas,  is  33.333 
inches  long.  The  chains  are  made  both  of  iron  and  steel 
wire,  ten  or  twenty  varas  in  length,  each  vara  being  usually 
divided  into  five  links.  A link,  including  a ring  at  each 
end,  is  therefore  6.666  inches  long.  A ten-vara  chain  has 
fifty  links  ; a twenty-vara  chain  one  hundred  links.  Each 
vara  is  marked  by  a round  brass  tally,  numbered  from  one 
to  nine  in  the  ten-vara  chain,  and  from  one  to  nineteen  in 
the  twenty-vara  chain. 

METER  CHAINS. 

The  meter  is  used  as  a standard  measure  of  length  in 
many  countries,  and  chains  of  ten  and  twenty  meters  are 
often  ordered.  The  chains  are  made  of  iron  or  steel  wire, 
each  meter  being  divided  into  five  links  ; a meter  being 
39.371  inches  long,  a link,  including  a ring  at  each  end,  is 
therefore  7.874  inches  long. 

A ten-meter  chain  has  fifty  links  and  a twenty-meter 
chain  one  hundred  links.  Each  meter  is  marked  with  a 
round  brass  tally  numbered  from  one  to  nine  in  the  ten- 


TAPES. 


237 


meter  chain  and  from  one  to  nineteen  in  the  twenty-meter 
chain. 

MARKING -PINS. 

In  chaining,  eleven  marking-pins  are  needed,  made  either 
of  iron,  steel  or  brass  wire,  as  may  be  preferred,  about 
fourteen  inches  long,  pointed  at  one  end  to  enter  the  ground, 
and  formed  into  a ring  at  the  other  end  for  convenience  in 
handling. 

Marking-  pins  are  sometimes  loaded  with  a little  mass 
of  lead  around  the  lower  end,  to  answer  as  a plumb  when 
dropped  to  the  ground  from  the  suspended  end  of  the 
chain. 

CHAIN-TAPES. 

Chain-tapes  are  made  of  a thin  ribbon  of  steel,  about 
one-quarter  of  an  inch  wide,  and  of  straight  spring-temper. 
They  are  usually  made  in  lengths  of  thirty-three  to  five 
hundred  feet  ; .and  are  generally  used  on  bridge,  road  and 
street  work,  and  also  as  standards  for  comparison  of  other 
chains  and  tapes. 

The  thirty-three  and  sixty-six  feet  lengths  are  usually 
graduated  at  each  Gunter’s  link  for  use  in  land-surveying  ; 
and  the  fifty  and  one  hundred  feet  lengths  are  graduated 
at  each  foot,  and  also  have  the  first  and  last  foot  marked  in 
tenths  for  city  work.  See  Price-List,  Nos.  760-767. 


NO.  760. 


A simple  and  convenient  reel  for  these  tapes  is  shown 
in  the  above  cut.  The  handle  of  the  drum  when  not  in 


238 


TAPES. 


use  can  be  folded  flat,  and  a small  projection  at  its  base  fits 
into  a slot  made  to  receive  it  and  thus  clamps  the  drum 
and  prevents  the  tape  from  unwinding. 


NO.  770. 


The  longer  tapes,  from  three  hundred  to  five  hundred 
feet  in  length,  are  usually  graduated  at  each  five  feet,  and 
also  have  the  first  and  last  five  feet  marked  at  each  foot. 
They  are  wound  upon  a substantial  wooden  reel,  with 
aluminum  and  brass  mountings,  as  shown  above.  See 
Price-List,  Nos.  770-772. 

Our  chain-tapes  are  U.  S.  Standard  measure  at  62°  Fahr- 
enheit and  with  ten  pounds  strain. 

METALLIC  TAPES. 

These  are  of  linen,  about  five-eighths  of  an  inch  wide, 
and  have  fine  brass  wires  interwoven  through  their  whole 
length.  They  are  thus  measurably  correct,  even  when  wet. 

They  are  graduated  in  feet  and  tenths  of  feet  or  in  feet 
and  inches,  on  one  side,  as  ordered,  and  are  also  marked  in 
links  on  the  reverse  side.  They  are  wound  up  in  a leather 
case  having  a folding  handle.  See  Price-List,  Nos.  780-794. 

STEEL  TAPES. 

The  best  tapes  are  made  of  a thin  ribbon  of  steel  in  one 
piece,  of  straight  spring-temper,  and  either  one-quarter, 
three-eighths,  or  one-half  of  an  inch  wide. 


TAPES : 


239 


These  tapes  are  of  all  lengths  from  twenty-five  to  one 
hundred  feet,  graduated  into  feet  and  inches,  and  links  on 
the  reverse  side,  or,  more  usually,  feet  and  tenths  of  a foot, 
and  links  on  the  reverse  side,  the  figures  and  graduations 
being  raised  on  the  surface  of  the  steel. 

Paine’s  American  steel  tapes  are  made  of  thin  steel  ribbon, 
straight  spring-temper,  in  one  piece,  and  about  one-quarter 
of  an  inch  wide.  They  can  be  detached  from  the  case  when 
desired,  and  used  with  a pair  of  handles  with  compensation- 
scale  for  variations  of  temperature,  for  chain  measurements. 

Paine’s  tapes  are  U.  S.  Standard  measure  at  62°  Fahren- 
heit, and  using  about  twelve  pounds  strain.  A hundred-foot 
tape  expands  .0756  inch  for  each  10°  rise  in  temperature. 

These  tapes  are  wound  up  in  a leather  or  metal  case,  as 
may  be  desired,  having  a folding  handle.  See  Price-List, 
Nos  800-835. 

Our  Excelsior  steel  tape,  one-half  inch  wide  and 
mounted  on  an  open  brass  frame  with  folding  handle,  is  well 
liked  for  use  in  mines. 

The  tape  is  easily  wound  up  and  unwound,  and  the 
open  frame  allows  moisture  to  evaporate.  See  Price-List, 
Nos.  850-858. 

METRIC  AND  VARA  TAPES. 

When  desired,  we  can  furnish  any  of  our  metallic  tapes, 
Nos.  780-794,  and  steel  tapes,  Nos.  800-835,  with  metric  or 
vara  measure  on  the  reverse  side,  instead  of  links,  at  extra 
prices,  as  quoted  on  pages  279  and  281  ; and  with  metric  or 
vara  measure  only,  at  prices  of  regular  styles  of  similar 
lengths  in  feet.  Our  chain-tapes,  Nos.  760-772,  are  also 
graduated  with  metric  measure  only  (when  so  ordered),  and 
are  marked  at  each  meter  with  the  first  and  last  meter  in 
decimeters. 


INFORMATION  TO  PURCHASERS. 


SELECTION  OF  INSTRUMENTS. 

T^OR  original  surveys,  or  ascertaining  the  bearing  of 
lines  in  the  preparation  of  county  maps,  the  Plain 
Compass  will  answer. 

The  Vernier  Compass,  or  Vernier  Transit-Compass, 
will  be  required  where  allowance  must  be  made  for  the 
variation  of  the  needle,  as  in  retracing  the  lines  of  an  old 
survey. 

When  local  attraction  must  be  taken  into  account,  in 
addition  to  the  variation  of  the  needle,  and  angles  taken 
independently  of  the  needle,  an  instrumenUwith  a gradu- 
ated limb  must  be  used,  and  for  this  purpose  the  Railroad 
Compass  will  be  sufficient. 

For  a mixed  practice  of  general  surveying,  including 
farm  and  city  work,  the  establishment  of  grades  of  roads 
and  the  running  of  levels,  such  an  instrument  as  the  Sur- 
veyors' Transit,  with  its  various  attachments,  is  amply 
sufficient. 

The  various  forms  of  the  Engineers’  Transit,  the 
Mountain  Transit,  and  the  Y-Leveling-Instruments, 
are  designed  for  engineering  of  the  highest  class. 

In  the  U.  S.  Public  Land  surveys,  an  instrument  with 
Solar  Attachment  is  required,  and  the  Solar  Transit  is 
usually  selected. 

In  surveys  of  mining  claims,  especially  in  high  eleva- 
tions, and  for  the  surveys  of  mines  in  general,  the  Moun- 
tain Transit,  with  the  Solar  Attachment  and  with  other 
extras,  has  proved  a universal  favorite. 


241 


242 


INFORMATION  TO  PURCHASERS. 


The  various  Plane-Table  outfits  have  a recognized 
utility  for  topographical  and  map  drawing. 

The  Current-Meters  are  almost  indispensable  in 
measuring  the  velocity  of  the  flow  of  water  in  harbors, 
rivers,  small  streams  and  irrigation  ditches. 

The  Drainage  Level  is,  we  believe,  the  most  simple 
and  efficient  instrument  designed  for  laying  out  drains  and 
similar  work. 

The  Architects’  Level  and  the  Builders’  Transit 
are  used  in  laying  out  buildings,  determining  the  level  of 
their  floors,  sills  and  windows,  and  in  the  general  work  of 
the  builder. 

The  Reconnoissance  Transit  and  the  various  forms  of 
Pocket  Compasses,  with  or  without  telescopic  attachment, 
are  very  desirable  for  a large  class  of  work  where  extreme 
lightness  and  portability  are  desirable. 

Where  iron  ores  are  to  be  traced,  the  Miners’  Dip-Com- 
pass, the  Dial  Compass  and  the  Pocket  Solar  Compass 
are  used.  We  do  not  pretend  to  make  any  instrument  by 
which  veins  of  gold  and  silver  can  be  traced,  or  the  pres- 
ence of  these  metals  detected. 

Our  instruments  are  not  carried  in  stock  by  merchants, 
and  we  do  not  deem  it  advisable  to  add  to  our  prices  in 
order  to  enable  us  to  give  to  merchants  a large  discount, 
which,  of  course,  would  be  paid  by  the  purchaser. 

WARRANTY. 

All  our  instruments  are  examined  and  tested  by  us  in 
person,  and  are  sent  to  the  purchaser  adjusted  and  ready 
for  immediate  use. 

When  purchased  directly  from  us,  they  are  warranted 
correct  in  all  their  parts,  — we  agreeing,  in  the  event  of  any 
defect  appearing  after  reasonable  use,  to  repair  or  replace 


INFORMATION  TO  PURCHASERS. 


243 


with  a new  and  perfect  instrument,  promptly  and  at  our 
own  cost,  express  charges  included  ; or  we  will  refund  the 
money  and  the  express  charges  paid  by  the  customer. 

Instances  sometimes  occur,  in  a business  as  large  and 
widely  extended  as  ours,  where,  owing  to  careless  transporta- 
tion or  to  defects  escaping  the  closest  scrutiny  of  the  maker, 
instruments  reach  our  customers  in  bad  condition.  We  con- 
sider the  retention  of  such  instruments  in  all  cases  an  injury 
very  much  greater  to  us  than  to  the  customer  himself. 

TRIAL  OF  INSTRUMENTS. 

It  may  happen  that  this  statement  will  come  into  the 
hands  of  those  who  are  entirely  unacquainted  with  us  or 
the  quality  of  our  work,  and  who  therefore  feel  unwilling 
to  purchase  an  instrument  of  the  excellence  of  which  they 
are  not  perfectly  assured. 

To  such  we  make  the  following  proposition  : If  re- 

quested to  do  so,  we  will  send  the  instrument  to  the  ex- 
press station  nearest  the  purchaser,  and  direct  the  Express 
Agent,  on  delivery,  to  collect  our  bill,  together  with  the 
charges  for  transportation,  and  hold  the  money  on  deposit 
one  or  two  weeks,  if  desired,  until  the  purchaser  shall  have 
had  an  actual  trial  of  the  instrument. 

If  not  found  as  represented,  the  purchaser  may  return 
the  instrument  before  the  expiration  of  the  specified  time, 
and  receive  the  money  paid  in  full,  including  express 
charges,  and  direct  the  instrument  to  be  returned  to  us. 

This  privilege  of  trial  applies  only  to  our  larger  Transits, 
Levels  and  Compasses,  and  is  not  given  unless  requested, 
and  is  allowed  only  in  the  United  States. 

EXTENT  OF  OUR  BUSINESS. 

Thousands  of  our  instruments  are  now  in  use  in  North 
and  South  America,  and  in  many  other  countries. 


244 


INFORMATION  TO  PURCHASERS. 


Our  facilities  for  manufacturing,  which  for  many  years 
have  been  far  superior  to  those  of  any  other  similar  estab- 
lishment, are  constantly  being  increased  by  the  introduction 
of  new  machinery  and  tools. 

We  make  under  our  own  roof  the  lenses  for  the  tele- 
scopes of  our  instruments,  the  glass  vials  for  the  level- 
tubes,  the  wooden  boxes  in  which  the  instruments  are 
packed,  the  leather  cases  and  straps  for  these  boxes,  as 
well  as  all  the  metal  parts  of  the  instruments  themselves. 

LOW  PRICE  OF  OUR  INSTRUMENTS. 

It  is  often  stated  that  it  is  impossible  to  make  first-rate 
instruments  at  our  prices,  which  are  far  below  those  of 
other  skillful  manufacturers.  To  this  we  can  only  reply 
that  a visit  to  our  works  and  a comparison  of  our  facilities 
with  those  of  any  manufacturer  will  dispel  all  doubts  as  to 
our  ability  to  furnish  the  best  instruments  for  the  money 
that  can  be  produced  in  this  country. 

PACKING. 

Each  of  our  Transits,  Levels  and  Surveyors’  Compasses 
is  packed  in  a well-finished  mahogany  case,  furnished  with 
lock  and  key  and  brass  hooks,  and  leather  strap  for  con- 
venience in  carrying.  Each  case  is  provided  with  screw- 
driver, adjusting-pin  and  wrench  for  center-pin,  and,  if 
accompanied  by  a tripod,  with  a brass  plummet.  With  all 
the  instruments  used  for  taking  angles  without  the  needle,  a 
. reading-glass  is  also  furnished. 

Unless  the  purchaser  is  already  supplied,  each  instru- 
ment is  accompanied  by  our  Manual,  giving  full  instruction 
for  such  adjustments  and  repairs  as  are  possible  to  one  not 
provided  with  the  facilities  of  an  instrument-maker. 

When  sent  to  the  purchaser,  the  mahogany  cases  are 


INFORMATION  TO  PURCHASERS. 


245 


carefully  enclosed  in  outside  packing-boxes  of  pine,  made  a 
little  larger  on  all  sides  to  allow  the  introduction  of  elastic  ‘ 
material  ; and  so  effectually  are  our  instruments  protected 
by  these  precautions,  that  of  many  thousands  sent  out 
since  1846,  in  all  seasons,  by  every  mode  of  transportation, 
and  to  all  parts  of  the  world,  very  few  have  sustained  any 
serious  injury. 

Instruments  packed  for  foreign  shipment,  which  are  to 
have  ocean  passage,  are  hermetically  sealed  in  tin  cases. 

MEANS  OF  TRANSPORTATION. 

Instruments  can  be  sent  by  express  to  almost  every 
town  in  the  United  States,  Canada,  and  Mexico,  regular 
agents  being  located  at  all  the  more  important  points,  by 
whom  they  are  forwarded  to  smaller  places  by  stage. 

The  charges  for  transportation  are  in  all  cases  to  be 
borne  by  the  purchaser,  we  guaranteeing  the  safe  arrival  of 
our  instruments  at  his  express-office,  and  holding  the  Ex- 
press Company  responsible  to  us  for  all  loss  and  damage 
on  the  way. 

FINISH  OF  INSTRUMENTS. 

All  instruments  are  covered  with  a lacquer  applied  when 
the  work  is  heated.  As  long  as  this  lacquer  remains,  the 
brass  surface  will  be  kept  from  tarnishing,  and  the  engineer, 
by  taking  care  not  to  rub  his  instrument  with  a dusty  cloth 
or  to  expose  it  to  the  friction  of  his  clothes,  can  preserve 
its  original  freshness  for  a long  time. 

Instead  of  the  ordinary  brass  finish,  most  engineers  pre- 
fer instruments  blackened  or  bronzed.  This  is  done  with 
an  acid  preparation,  after  the  work  has  been  polished,  and 
gives  the  instrument  a very  showy  appearance,  besides  being 
advantageous  on  account  of  not  reflecting  the  rays  of  the 
sun  as  much  as  the  bright  or  brass  finish. 


246 


INFORMATION  TO  PURCHASERS. 


If  no  direction  is  given,  we  usually  send  Transits,  Levels, 
and  Solar  instruments  of  bronze  finish,  and  Compasses  of 
bright  finish. 

TERMS  OF  PAYMENT. 

Our  terms  of  payment  are  uniformly  cash,  and  we  have 
but  one  price,  whether  ordered  in  person,  by  mail  or  tele- 
graph. Our  prices  are  as  low  as  instruments  of  first  quality 
can  be  made. 

Remittances  may  be  made  by  a cashier's  draft  payable 
to  our  order,  which  can  be  procured  from  banks  or  bankers 
in  almost  all  the  larger  villages,  or  by  Express  Company  or 
Post-office  money-orders.  These  may  be  sent  by  mail  with 
the  order  for  the  instrument,  and  if  lost  or  stolen  on  the 
way  can  be  replaced  by  a duplicate  obtained  as  before, 
without  additional  cost.  The  customer  may  also  send  the 
money  in  advance  by  registered  mail  or  by  the  express 
agent,  or  may  pay  the  agent  on  receipt  of  the  instrument 
in  funds  current  in  New  York. 

Customers  ordering  instruments  and  desiring  changes 
in  construction  from  our  regular  patterns  must  make  a 
payment  in  advance,  when  ordering,  of  fifty  per  cent,  of 
the  price. 

The  cost  of  returning  the  money  on  bills  of  amounts 
under  $20,  collected  by  express,  will  be  charged  to  the 
customer. 

When  articles  are  to  be  sent  by  mail,  payment  must  be 
made  in  advance,  including  the  cost  of  postage.  The 
postage  required  is  mentioned  in  the  second  column  of  the 
Price-List. 

INSTRUMENTS  FOR  FOREIGN  COUNTRIES. 

We  send  Civil  Engineers’  and  Surveyors’  instruments  to 
Canada,  Mexico,  Central  America,  Cuba,  South  America, 


INFORMATION  TO  PURCHASERS. 


247 


China,  Japan,  Australia,  Africa,  and  India,  as  well  as  to 
various  parts  of  Europe. 

The  cash  for  all  orders  for  foreign  shipments  by  steam- 
ship must,  in  every  case,  accompany  the  order,  and  if  it  is 
desired  that  we  attend  to  the  shipment  of  the  instruments, 
the  remittance  must  be  made  ten  per  cent,  more  than  the 
catalogue  price  of  the  instruments  if  the  order  amounts  to 
$250  or  less,  or  eight  per  cent,  more  than  the  catalogue 
price  if  the  order  amounts  to  from  $300  to  $500,  or  six  per 
cent,  more  than  the  catalogue  price  if  the  order  amounts  to 
from  $600  to  $1,000.  This  extra  remittance  is  to  cover 
cost  of  shipping  charges,  freight  and  insurance,  which  must 
always  be  paid  in  advance  on  all  shipments  except  those 
to  Canada  and  some  parts  of  Mexico. 

If  the  amount  remitted  is  more  than  enough  to  cover 
these  expenses,  any  balance  will  be  returned  to  the  pur- 
chaser with  the  receipted  bill  and  bill  of  lading,  unless  we 
are  directed  to  hold  it  to  his  credit  and  subject  to  his  order. 

Remittances  must  be  made  by  bankers’  draft  on  Lon- 
don, England,  or  on  New  York  City,  and  such  drafts  can 
be  purchased  in  any  of  the  large  cities  of  the  countries 
named. 

When  telegraphing  cable  messages  to  us,  use  either  the 
Western  Union  or  the  Lieber  Code. 

AL  UMINUM. 

Since  1876  we  have  been  making  Civil  Engineers’  and 
Surveyors’  instruments  of  aluminum,  to  order  only.  The 
only  advantage  which  instruments  of  aluminum  have  over 
those  of  the  ordinary  metals  is  their  light  weight ; but  as 
all  the  bearing  parts  must  be  made  of  bronze,  the  total 
weight  can  be  reduced  only  about  fifty  per  cent.  We  finish 
our  aluminum  instruments  in  the  natural  color,  and  the 
% 


248  INFORMATION  TO  PURCHASERS. 

result  is  more  satisfactory  from  an  artistic  standpoint  than 
when  an  artificial  coloring  is  used,  although  it  entails  much 
extra  expense.  We  will  quote  prices  on  application  for  any 
of  our  instruments  of  regular  pattern  made  of  aluminum. 

REPAIR  OF  INSTRUMENTS. 

Every  year  we  receive  a thousand,  or  more,  instruments 
of  our  own  and  others’  make,  sent  to  us  for  refitting  and 
repairs.  Most  of  them  have  been  injured  by  falls,  many 
have  parts  worn  and  defective  after  long  use  ; and  others 
are  sent  for  repolishing  and  renovating. 

The  injuries  are  usually  more  serious  than  is  apparent  to 
the  owner,  and  the  full  extent  of  the  injury  can  be  known 
only  by  an  examination  as  the  instrument  is  taken  apart. 

We  advise  our  customers  who  have  instruments  in  need 
of  repairs  to  send  them  directly  to  us,  as  our  facilities 
enable  us  to  do  the  work  much  more  economically  and 
promptly  than  any  other  maker,  however  accessible. 

The  instruments  should  always,  when  practicable,  be 
placed  in  their  own  boxes,  and  then  enclosed  in  an  outside 
packing  case,  an  inch  larger  in  all  its  dimensions,  that  the 
space  between  the  two  may  be  filled  with  paper  wadding, 
hay  or  fine  shavings.  The  owner’s  name  and  address 
should  always  appear  on  the  package,  and  a note  specify- 
ing the  repairs  needed  should  always  accompany  the  instru- 
ment, and  a letter  should  also  be  sent  to  us  by  mail,  giving 
not  only  directions  as  to  the  repairs,  but  also  stating  when 
the  return  of  the  instrument  is  desired,  and  the  address  to 
which  it  should  be  forwarded. 

It  should  also  be  remembered  that  each  instrument  is 
made  to  fit  its  own  spindle,  and  no  other  ; and  therefore 
this  part,  with  the  leveling-plates  and  leveling-screws,  if  it 
has  them,  should  always  be  sent  with  it.  The  tripod  legs 


i 


INFORMATION  TO  PURCHASERS. 


249 


and  the  head  in  which  they  are  inserted  need  not  be  sent, 
unless  in  need  of  repairs.  When  requested  to  do  so,  we 
will  send  an  estimate  of  the  cost  of  repairs  on  any  instru- 
ment sent  us,  before  beginning  the  work. 

Compasses  come  to  us  with  the  plates  sprung,  the  sights 
bent  or  broken,  the  glass  or  level-vials  fractured,  and  the 
repairs  to  pivot  so  dulled  as  to  render  the  needle  slug- 
com passes,  gish  and  unreliable.  The  cost  of  repairing 
these  defects  ranges  from  $2  to  $10.  A pair  of  new  sights 
fitted  costs  $5  ; a new  needle  with  jeweled-center  and  pivot 
complete,  $3  ; a new  jeweled-center  only,  $1.50  ; regradu- 
ating compass-circle,  $5.  The  Compass  should  always  be 
accompanied  with  the  ball-spindle,  and  if  a new  ball-spindle 
is  required,  the  whole  instrument,  or  at  least  the  socket  in 
which  the  spindle  fits,  should  be  forwarded  to  us.  A new 
ball-spindle,  fitted,  costs  $2.  See,  also,  page  253. 

Repairs  to  Railroad  Compasses  cost  from  $10  to  $20, 
and  to  Solar  Compasses  from  $20  to  $50  ; and  regraduat- 
ing the  horizontal  limb  and  vernier  to  read  to  one  minute, 
costs  $10. 

The  injuries  which  Engineers’  and  Surveyors’  Transits 
sustain  by  falls  are  usually  much  more  serious  ; the  plates, 
repairs  TO  standards  and  cross-bars  of  telescopes  are 
transits.  often  bent,  and  sockets  or  centers  are  usually 
so  deranged  as  to  be  entirely  useless. 

The  cost  of  repairing  an  instrument  with  such  injuries 
ranges  from  $10  to  $30,  or  even  $50,  new  sockets  alone  cost- 
ing from  $15  to  $20.  See,  also,  page  253. 

Variation  plate  added  to  an  Engineers’  Transit  sent 


for  repairs,  costs $15.00 

Regraduating  horizontal  limb  and  vernier  to  read  to 

one  minute,  costs  10.00 

Regraduating  vertical  limb  and  vernier  to  read  to  one 

minute,  costs 5.00 


250 


INFORMATION  TO  PURCHASERS. 


No  one  but  a workman  with  practised  hand  and  pro- 
vided with  the  best  facilities  can  properly  set  the  platinum 
platinum  wires  in  a cross- wire  diaphragm,  and  it  is 
cross-wires,  useless,  therefore,  for  us  to  send  a parcel 
of  wires  for  that  purpose. 

The  only  way  in  which  they  can  be  replaced  without 
sending  the  telescope  to  us  is  to  take  out  the  ring  and  send 
it,  with  its  screws,  washers,  etc.,  and  we  will  return  it  with 


the  wires,  properly  secured. 

Plain  platinum  cross-wires,  replaced  on  the  old  ring, 

cost $2.00 

Adjustable  platinum  stadia-wires,  replaced  on  the  old 

ring,  cost 3.00 

Fixed  platinum  stadia-wires,  replaced  on  the  old  ring, 

cost 5.00 


If  sent  by  mail,  add  15  cents  for  postage  and  registry, 
and  25  cents  for  a safety  brass  packing-box. 

We  are  not  responsible  for  wires  sent  in  this  way  and 
broken  while  inserting  the  ring  in  the  telescope.  The  best 
plan  is  to  send  us  .the  telescope  when  new  cross-wires  are 
needed. 

When  it  is  desirable  to  substitute  platinum  for  spider- 
web, a new  ring  with  screws  will  be  required,  and  the  tele- 
scope should  be  sent  to  us. 

Plain  platinum  cross- wires,  with  diaphragm,  screws, 


etc.,  cost... $3.00 

Adjustable  platinum  stadia-wires,  with  diaphragm, 

screws,  etc.,  cost 5.00 

Fixed  platinum  stadia-wires,  with  diaphragm,  screws, 

etc.,  cost 7.00 

( See,  also,  pages  9-11.) 


Leveling-instruments  are  generally  much  less  injured 
repairs  to  by  falls  than  Transits.  The  damages  are 
levels.  usually  the  bending  of  the  bar,  the  springing 
of  the  sockets,  and  the  breaking  of  the  vial. 


INFORMATION  TO  PURCHASERS. 


251 


The  cost  of  repairs  varies  from  $5  to  $20  ; a new  level- 
vial  set  in  the  old  tube  costs  $1.25  to  $2.50,  according  to 
size  of  the  Level.  See,  also,  page  254. 
repolishing  The  cost  of  repolishing  an  instrument 
instruments,  varies,  but  may  be  stated  generally  as 
follows : 


Compasses,  Plain  and  Vernier $ 5.00  to  $ 7.00 

Railroad  Compasses 8.00  to  10.00 

Solar  Compasses,  large  size  12.00  to  15.00 

Transits 12.00  to  15.00 

Y- Levels 8.00  to  12.00 


It  must  be  understood  that  these  prices  are  in  addition 
to  the  cost  of  adjustment  and  of  any  necessary  repairs. 

No  additional  charge  is  made  for  bronzing  or  blackening 
an  instrument  when  repolished. 

Payment  for  repairs  may  be  made  at  the  Express-Office 
where  the  instrument  is  received,  the  customer  paying  for 
the  first  transportation  of  the  instrument  to 

PAYMENT. 

us  or  not,  as  he  may  prefer,  whenever  the 
charges  are  paid  in  advance  the  express  receipt  should  be 
mailed  directly  to  us. 

W.  & L.  E.  GURLEY, 

Mathematical  Instrument  Makers, 

514  Fulton  St.,  opposite  North  End  of  Union  R.  R.  Depot, 

Troy,  N.  Y.,  U.  S.  A. 


I 


\ 


/ 


' 


J 


/ 


W.  & L.  E.  GURLEY,  TROY,  N.  Y.  253 

PRICES  FOR  PARTS  OF  INSTRUMENTS 
LIABLE  TO  LOSS  OR  INJURY. 

FOR  TRANSITS. 

Price.  Post. 

Needle  with  jeweled-center  and  center-pin $3.00  $0.10 

Center-pin  only .50  .01 

Ground  glass  level -vial  for  plate  or  standard,  each .35  .02 

Ground  glass  level-vial,  brass  mounted  complete,  for  plate 

or  standard,  each 2.00  .12 

Ground  glass  level-vial  for  telescope,  each 1.25  .12 

Cap  for  eyepiece  or  object-glass,  each .75  .03 

Shade  for  object-glass .75  .03 

Clamp-screws  for  horizontal  limb,  each .75  .02 

Tangent  screw  for  leveling-head $0.75  to  1.50  .11 

Clamp-screw  for  leveling-head .75  .03 

Leveling-screw  for  leveling-head,  each $1.00  to  1.50  .12 

Eyepiece  complete 6.00  .12 

Object-glass  complete 6.00  .12 

Platinum  cross- wires  and  diaphragm 3.00  .15 

Platinum  stadia  wires,  adjustable,  and  diaphragm 5.00  .15 

Platinum  stadia  wires,  fixed,  and  diaphragm 7.00  .15 

Mahogany  box  with  lock  and  strap,  and  fitted  inside $4  to  $6 

FOR  SURVEYORS’  COMPASSES. 

Needle  with  jeweled-center  and  center-pin $3.00  $0.10 

Center-pin  only .50  .01 

Plain  glass  level-vials,  each .12  .02 

Plain  glass  level-vials,  brass  mounted  complete,  each 1.50  .12 

Brass  cover  for  Compass  of  our  make 1.00  .25 

Outkeeper 1.00  .11 

Glass  circle  for  compass-face .25  .15 

Wrench  for  center-pin .10  .01 

Staff  mountings,  brass  head,  without  spindle 2.00  .25 

Staff  mountings,  steel  point .50  .18 

Ball-spindle,  fitted  to  old  socket 2.00  .30 

Compass  sight-vanes,  each 2.50  .20 

Clamp-screw  for  spindle  or  sight-vane .50  .03 

Tangent  screw  for  moving  vernier 1.50  .10 

Staff  mountings  complete  for  Pocket-Compass,  small 2.50  .15 

Staff  mountings  complete  for  Pocket-Compass,  large 3.50  .20 

Mahogany  box  with  lock  and  strap,  and  fitted  inside $4  to  $6 


254 


IV.  &>  L.  E.  GURLEY,  TROY,  N.  Y 


FOR  Y-LEVELS. 

Price.  Post. 

Ground  glass  level- vial,  unmounted,  for  22-inch  Y-Level...  $1.85  $0.15 

Ground  glass  level-vial,  unmounted,  for  15-20- inch  Y-Levels  1.65  .15 

Ground  glass  level-vial,  extra  sensitive  (ten  seconds  in  one- 
tenth  of  one  inch),  unmounted,  for  18,  20  or  22-inch 

Y-Levels 4.00  .15 

Ground  glass  level-vial,  unmounted  for  Architects’  Level...  .90  .05 

Cap  for  eyepiece  or  object-glass,  each .75  .03 

Clamp-screw  for  leveling-head .75  .03 

Tangent  screw  for  leveling-head $0.75  to  1.50  .11 

Leveling-screw  for  leveling-head,  each 1.00  to  1.50  .12 

Eyepiece  complete 6.00  .12 

Object-glass  complete 7.00  .12 

Platinum  cross-wires  and  diaphragm 3.00  .15 

Platinum  stadia  wires,  adjustable,  and  diaphragm 5.00  .15 

Platinum  stadia  wires,  fixed,  and  diaphragm 7.00  .15 

Mahogany  box,  with  lock  and  strap,  and  fitted  inside $4.50  to  $6. 

MISCELLANEOUS. 

Plain  tripod  legs  only,  for  Engineers’  Transit  or  Level,  per  set  $5.00 
Split  tripod  legs  only,  for  Engineers’  Transit  or  Level,  per  set  7.00 
Extension  tripod  legs  only,  for  Engineers’  Transit  or  Level, 

per  set 10.00 

Clamp-screw  and  band  for  extension  leg,  each .85  $0.05 

Tripod  head  only,  with  bolts  and  nuts,  for  Engineers’ 

Transit  or  Level 5.00  .50 

Wooden  cap  with  brass  screw-plate,  to  fit  tripod  head,  each  .75  .12 

Brass  bolt  and  nut  to  fit  tripod  head,  each .50  .05 

Metal  point  or  shoe  for  tripod  leg,  each .50  .05 

Leather  ring  to  bind  tripod  legs  together,  each .10  .02 

Leather  strap  and  buckle  for  Transit  or  Level  box .50  .15 

Leather  strap  and  handle  for  carrying  extension  tripod .50  .10 

Steel  screw-driver  with  wooden  handle,  each .15  .03 

Steel  adjusting-pins,  each .05  .01 

Rubber  tips,  for  bottom  of  instrument-box,  per  set... .40  .08 

Reading-glass,  for  Transit,  each .75  .02 

Brass  Plummet  with  screw  cap,  for  Transit  or  Level,  each..  1.50  .20 

Waterproof  hood,  for  Transit  or  Level,  each 1.00  .12 

Chamois  skin,  large  size,  best  quality,  each .65  .05 

Clamp  with  clamp-screw,  for  New  York  rod 2.00  .15 

Clamp  with  scale  and  clamp-screw,  for  Philadelphia  rod...  2.50  .15 

Target  with  clamp-screw  and  spring,  for  New  York  or 

Philadelphia  rod 5.00  .35 

Chain  handle,  with  staple  and  nuts,  each .75  .08 

Chain  tallies,  per  set  of*9 .50  .06 


256 


W.  6°  L.  E.  GURLEY,  TROY,  N.  Y. 


SPECIAL  NOTICE. 

A Transit  with  “plain”  telescope  is  one  without  any  attachments  or 
extras,  such  as  the  clamp  and  tangent,  vertical  circle  and  level. 

All  our  Transits,  Nos.  1 to  105,  are  furnished  with  shifting  center  to  the 
leveling-head,  and  with  a tripod  and  leveling-screws  and  clamp  and  tan- 
gent to  spindle. 

The  limbs  of  all  our  Transits,  Nos.  1 to  102,  are  graduated  on  sterling 
silver.  The  graduation  is  to  half  degrees,  and  is  read  by  vernier  to  single 
minutes.  A finer  graduation  is  furnished,  if  desired,  at  an  extra  price. 
See  page  262. 

The  vertical  circles  and  vertical  arcs  are  also  graduated  on  sterling 
silver.  The  circle  of  3J-inch  diameter  is  graduated  to  whole  degrees  and 
is  read  by  vernier  to  5 minutes.  The  circle  of  4J-inch  diameter  and  the 
arc  of  2J-inch  radius,  are  graduated  to  half  degrees  and  are  read  by  vernier 
to  1 minute.  The  arc  of  3-inch  radius  is  graduated  to  20  minutes  and  is 
read  by  vernier  to  30  seconds. 

A variation  arc  furnished  with  any  new  Engineers’  Transit,  Nos.  1 to 
16,  costs  extra  $4.00.  See  No.  130,  page  261. 

All  our  Transits,  Nos.  35  to  102,  and  110  to  117,  have  a variation  arc 
for  setting  off  the  variation  of  the  needle. 

A leveling-tripod  head  with  plates,  levelingrscrews  and  clamp  and  tan- 
gent movement,  fitted  to  Vernier  Transits,  costs  extra  $13.00.  See  No. 
176,  pages  123  and  262. 

If  requested,  when  ordering  a new  Transit,  we  furnish  stadia  wires  in 
the  telescope,  dust  guard  to  the  object-glass  slide  and  reflectors  to  the  limb 
verniers,  without  extra  charge.  When  desired,  we  arrange  the  stadia  wires 
to  disappear,  or  be  out  of  focus,  when  the  plain  cross-wires  only  are  in  use. 

Each  Transit  is  packed  in  a mahogany  case,  with  lock  and  leather 
strap,  and  has  a plummet,  reading-glass,  adjusting-pins,  etc. 


PRICE-LIST. 

THIRTY-SIXTH  EDITION. 


All  Prices  in  this  work  are  in  U.  S.  Currency.  State  what  Edition  of 
Manual  when  ordering  goods,  and  give  Catalogue  Number. 


TZiis  Price-List  supersedes  all  previous  Editions . 

ENGINEERS’  TRANSITS. 

No.  Price. 

1.  Engineers’  Transit,  two  verniers  to  limb,  4-inch  needle, 

plain  telescope $145.00 

2.  Engineers’  Transit,  two  verniers  to  limb,  4-inch  needle, 

with  level  on  telescope  and  clamp  and  tangent  to  tele- 
scope axis , 163.00 

3.  Engineers’  Transit,  two  verniers  to  limb,  4-inch  needle, 

with  4£-inch  vertical  circle,  level  on  telescope  and  clamp 

and  tangent  to  telescope  axis 175.00 

6.  Engineers’  Transit,  two  verniers  to  limb,  4J-inch  needle, 

plain  telescope 150.00 

7.  Engineers’  Transit,  two  verniers  to  limb,  4J-inch  needle, 

with  level  on  telescope  and  clamp  and  tangent  to  tele- 
scope axis 168.00 

8.  Engineers’  Transit,  two  verniers  to  limb,  4J-inch  needle, 

with  4J-inch  vertical  circle,  level  on  telescope  and  clamp 

and  tangent  to  telescope  axis 180.00 

9.  Engineers’  Transit,  two  verniers  to  limb,  4J-inch  needle, 

with  vertical  arc  of  3 inches  radius  and  vernier  moved  by 
tangent  screw,  level  on  telescope  and  clamp  and  tangent 

to  telescope  axis 186.00 

10.  Engineers’  Transit,  two  verniers  to  limb,  4J-inch  needle, 
with  vertical  arc  of  3 inches  radius  and  vernier  moved  by 
tangent  screw,  level  on  telescope  and  gradienter  com- 
bined with  clamp  and  tangent  to  telescope  axis 198.00 

12.  Engineers’  Transit,  two  verniers  to  limb,  5-inch  needle, 

plain  telescope,  as  shown  on  page  6 150.00 

13.  Engineers’  Transit,  two  verniers  to  limb,  5-inch  needle, 

with  level  on  telescope  and  clamp  and  tangent  to  tele- 
scope axis 168.00 

14.  Engineers’  Transit,  two1  verniers  to  limb,  5-inch  needle, 

with  4J-inch  vertical  circle,  level  on  telescope  ^nd  clamp 

and  tangent  to  telescope  axis 180.00 

257 


258 


W.  6-  L.  £.  GURLEY,  TROY,  N.  K 


ENGINEERS’  TRANSITS.—  Concluded. 

No.  Price. 

15.  Engineers’  Transit,  two  verniers  to  limb,  5-inch  needle, 

with  vertical  arc  of  3 inches  radius  and  vernier  moved  by 
tangent  screw,  level  on  telescope  and  clamp  and  tangent 
to  telescope  axis $186.00 

16.  Engineers’  Transit,  two  verniers  to  limb,  5-inch  needle, 

with  vertical  arc  of  3 inches  radius  and  vernier  moved  by 
tangent  screw,  level  on  telescope  and  gradienter  com- 
bined with  clamp  and  tangent,  as  shown  on  page  26 198.00 

17.  Engineers’  Transit,  two  verniers  to  limb,  5-inch  needle, 

with  variation  arc,  Solar  Attachment,  vertical  arc  of  3 
inches  radius  and  vernier  moved  by  tangent  screw,  level 
on  telescope,  and  clamp  and  tangent  to  telescope  axis, 
as  shown  on  page  28 250.00 


LIGHT  MOUNTAIN  AND  MINING  TRANSITS. 

25.  Light  Mountain  Transit,  two  verniers  to  limb,  4-inch 
needle,  with,  variation  arc,  telescope  of  finest  quality, 
power  20  diameters,  extension  tripod  shortening  to  half 
length.  The  instrument  is  packed  in  a mahogany  case, 
covered  with  a light  sole-leather  case,  with  straps  for 


“packing.”  With  plain  telescope $150.00 

26.  Light  Mountain  Transit,  with  level  on  telescope  and  clamp 

and  tangent  to  telescope  axis 168.00 

27.  Light  Mountain  Transit,  with  4J-inch  vertical  circle,  level 

on  telescope  and  clamp  and  tangent  to  telescope  axis 180.00 

28.  Light  Mountain  Transit,  with  vertical  arc  of  2J-  inches 

radius  and  vernier  moved  by  tangent  screw,  level  on  tele- 
scope and  clamp  and  tangent  to  telescope  axis 186.00 

29.  Light  Mountain  Transit,  with  vertical  arc  of  2J  inches 

radius  and  vernier  moved  by  tangent  screw,  level  on  tele- 
scope and  gradienter  combined  with  clamp  and  tangent...  198.00 

30.  Light  Mountain  Transit,  with  Solar  Attachment,  vertical 


arc  of  2J  inches  radius  and  vernier  moved  by  tangent 


screw,  level  on  telescope  and  clamp  and  tangent  to  tele- 
scope axis,  as  shown  on  page  31 245.00 

31.  Light  Mountain  Transit,  with  Solar  Attachment,  Jones’ 
latitude  arc  complete,  level  on  telescope  and  clamp  and 
tangent  to  telescope  axis.  See  page  83 300.00 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y 259 

SURVEYORS’  TRANSITS. 

No.  (WITH  TWO  VERNIERS  TO  LIMB.)  Price. 

35.  Surveyors’  Transit,  two  verniers  to  limb,  4-inch  needle, 

plain  telescope $125.00 

36.  Surveyors’  Transit,  two  verniers  to  limb,  4-inch  needle, 

with  level  on  telescope  and  clamp  and  tangent  to  tele- 
scope axis 143.00 

37.  Surveyors’  Transit,  two  verniers  to  limb,  4-inch  needle, 

with  4£-inch  vertical  circle,  level  on  telescope  and  clamp 

and  tangent  to  telescope  axis 155.00 

45.  Surveyors’  Transit,  two  verniers  to  limb,  5-inch  needle, 

plain  telescope — \ 130.00 

46.  Surveyors’  Transit,  two  verniers  to  limb,  5-inch  needle, 

with  level  on  telescope  and  clamp  and  tangent  to  tele- 
scope axis 148.00 

47.  Surveyors’  Transit,  two  verniers  to  limb,  5-inch  needle, 

with  4J-inch  vertical  circle,  level  on  telescope  and  clamp 

and  tangent  to  telescope  axis,  as  shown  on  page  34 160.00 

48.  Surveyors’  Transit,  two  verniers  to  limb,  5-inch  needle, 

with  4J-inch  vertical  circle,  level  on  telescope  and  gradi- 

enter  combined  with  clamp  and  tangent  to  telescope  axis..  172.00 

55.  Surveyors’  Transit,  same  as  No.  45,  but  with  5J-inch 

needle 130.00 

56.  Surveyors’  Transit,  same  as  No.  46,  but  with  5J-inch 

needle 148.00 

57.  Surveyors’  Transit,  same  as  No.  47,  but  with  5J-inch 

needle 160.00 

58.  Surveyors’  Transit,  same  as  No.  48,  but  with  5J-inch 

needle 172.00 

60.  Surveyors’  Transit,  two  verniers  to  limb,  5-inch  needle, 
with  Solar  Attachment,  vertical  arc  of  3 inches  radius  and 
vernier  moved  by  tangent  screw,  level  on  telescope  and 
clamp  and  tangent  to  telescope  axis,  as  shown  on  page  41..  226.00 


260 


W.  & L.  E.  GURLEY,  TROY,  N.  Y 

SURVEYORS’  TRANSITS. 

No.  (WITH  ONE  VERNIER  TO  LIMB.)  Price. 

65.  Surveyors’  Transit,  one  vernier  to  limb,  4-inch  needle, 

plain  telescope $110.00 

66.  Surveyors’  Transit,  one  vernier  to  limb,  4-inch  needle,  with 

level  on  telescope  and  clamp  and  tangent  to  telescope 

axis 128.00 

67.  Surveyors’  Transit,  one  vernier  to  limb,  4-inch  needle,  with 

4J-inch  vertical  circle,  level  on  telescope  and  clamp  and 
tangent  to  telescope  axis 140.00 

75.  Surveyors’  Transit,  one  vernier  to  limb,  5-inch  needle, 

plain  telescope 115.00 

76.  Surveyors’  Transit,  one  vernier  to  limb,  5-inch  needle,  with 

level  on  telescope  and  clamp  and  tangent  to  telescope 

axis,  as  shown  on  page  38 133.00 

77.  Surveyors’  Transit,  one  vernier  to  limb,  5-inch  needle,  with 

4J-inch  vertical  circle,  level  on  telescope  and  clamp  and 
tangent  to  telescope  axis 145.00 

78.  Surveyors’  Transit,  one  vernier  to  limb,  5-inch  needle,  with 

4^ -inch  vertical  circle,  level  on  telescope  and  gradienter 
combined  with  clamp  and  tangent  to  telescope  axis 157.00 

85.  Surveyors’  Transit,  same  as  No.  75,  but  with  5J-inch 

needle 115.00 

86.  Surveyors’  Transit,  same  as  No.  76,  but  with  5J-inch 

needle 133.00 

87.  Surveyors’  Transit,  same  as  No.  77,  but  with  5J-incli 

needle 145.00 

88.  Surveyors’  Transit,  same  as  No.  78,  but  with  5 J -inch 

needle...: ...; 157.00 

90.  Surveyors’  Transit,  one  vernier  to  limb,  5-inch  needle,  with 
Solar  Attachment,  vertical  arc  of  3 inches  radius  and 
vernier  moved  by  tangent  screw,  level  on  telescope  and 
clamp  and  tangent  to  telescope  axis,  as  shown  on  page  41  211.00 

RECONNOISSANCE  TRANSIT. 

100.  Reconnoissance  Transit,  one  vernier  to  limb,  3J-inch 
needle,  with  3J-inch  vertical  circle,  level  on  telescope 
and  clamp  and  tangent  to  telescope  axis,  leveling-screws 
and  clamp  and  tangent  to  spindle,  and  extension  tripod, 

as  shown  on  page  43 $115.00 

102.  Reconnoissance  Transit,  same  as  No.  100,  but  with 

4J-inch  vertical  circle  and  vernier  reading  to  one  minute..  122.00 


W.  6-  L.  E.  GURLEY, , TROY,  N.  Y 


261 


BUILDERS’  TRANSIT. 

No.  . Price. 

105.  Builders’  Transit,  with  level  on  telescope,  clamp  and  tan- 
gent to  telescope  axis  and  to  limb  and  spindle,  and  with 
leveling-screws  and  tripod,  as  shown  on  page  45 $80.00 

VERNIER  TRANSIT-COMPASSES. 

110.  Vernier  Transit,  5-inch  needle,  plain  telescope,  compass 

tripod $70.00 

111.  Vernier  Transit,  5-inch  needle,  with  level  on  telescope  and 

clamp  and  tangent  to  telescope  axis 88.00 

112.  Vernier  Transit,  5-inch  needle,  with  3 J-inch  vertical  circle, 

level  on  telescope  and  clamp  and  tangent  to  telescope 

axis 96.00 

115.  Vernier  Transit,  6-inch  needle,  plain  telescope,  compass 

tripod 75.00 

116.  Vernier  Transit,  6-inch  needle,  with  level  on  telescope  and 

clamp  and  tangent  to  telescope  axis 93.00 

117.  Vernier  Transit,  6-inch  needle,  with  3J-inch  vertical 

circle,  level  on  telescope,  and  clamp  and  tangent  to 
telescope  axis,  as  shown  on  page  47 101.00 


ATTACHMENTS  AND  EXTRAS  FOR  TRANSITS. 


No.  Price.  Post. 

130.  Variation  Arc  added  to  any  new  Engineers’  Transit, 

Nos.  1 to  16,  if  ordered  with  the  Transit $ 4.00 

131.  Variation  Arc  added  to  Transits  when  sent  for  re- 

pairs  15.00 

135.  Vertical  Circle,  3J  inches  diameter,  with  vernier  to 

5 minutes,  see  pages  49  and  50 8.00  $0.15 

136.  Vertical  Circle,  4£  inches  diameter,  with  vernier  to 

1 minute,  see  page  49 12.00  .20 

137.  Vertical  Circle,  5 inches  diameter,  with  vernier  to 

1 minute 15.00  .20 

138.  Vertical  Circle,  5 inches  diameter,  with, two  opposite 

double  verniers  to  1 minute,  see  page  51 35.00  .35 

139.  Vertical  Arc,  2J  inches  radius,  with  vernier  to  1 

minute  moved  by  tangent  screw,  see  page  52 18.00  .20 

140.  Vertical  Arc,  3 inches  radius,  with  vernier  to  30 

seconds  moved  by  tangent  screw,  see  page  52 18.00  .20 

145.  Level  on  Telescope  with  ground  vial  and  scale,  see 

page  53.. 12.00  .25 

148.  Clamp  and  Tangent  to  telescope  axis,  see  page  53...  6.00  .13 

150.  Gradienter  combined  with  clamp  and  tangent,  see 

page  56 18.00  .25 

151.  Platinum  Stadia  wires,  adjustable,  and  diaphragm...  5.00  .15 

152.  Platinum  Stadia  wires,  fixed,  and  diaphragm 7.00  #/15 


262  IV.  &•  L.  E.  GURLEY,  TROY,  N.  V. 

ATTACHMENTS  AND  EXTRAS  FOR  TRANSITS. — Concluded. 

No.  Price.  Post. 

154.  Dust-Guard  to  object-glass  slide,  see  page  12 $4.00 

155.  Rack  and  Pinion  movement  to  eyepiece 5.00  * 

157.  Sights  on  Telescope  with  folding  joints,  see  page  54  8.00 

158.  Sights  on  Standards  at  right  angles  with  telescope, 

see  page  55 8.00 

160.  Detachable  Side  Telescope  and  Counterpoise,  for 

vertical  sighting,  see  page  58 25.00  $0.50 

161.  Detachable  Riding  Telescope,  for  vertical  sighting, 

see  page  58 25.00  .50 

165.  Reflector  for  illuminating  cross- wires,  see  page  59...  4.00  .10 

168.  Diagonal  Prism  for  eyepiece  of  telescope,  see  page  59  8.00  .10 

170.  Plummet- Lamp  for  Mine-Engineering,  see  page  60..  10.00  .35 

173.  Quick-Leveling  Attachment 6.00  .35 

174.  Quick-Leveling  Attachment,  if  ordered  with  any 

new  Transit  Nos.  1 to  105 5.00 

176.  Leveling-Head  with  parallel  plates,  leveling-screws 
and  clamp  and  tangent,  fitted  to  Transits  Nos. 

110  to  117,  see  page  123 13.00 

180.  Attached  Magnifier,  with  universal  joint,  to  read 

verniers,  each 5.00 

185.  Graduation  of  limb  to  read  to  20  or  30  seconds, 

extra 10.00 

186.  Graduation  of  limb  to  read  to  10  seconds,  extra 30.00 

187.  Graduation  of  4J  or  5-inch  vertical  circle  to  read  to 

20  or  30  seconds,  extra 5.00 

190.  Solar  Attachment  with  declination  arc,  hour-circle 

and  polar  axis,  see  page  61 60.00  .30 

192.  Solar  Screen  to  fit  eyepiece  of  telescope,  see  page  80  5.00  .12 

193.  Patent  Latitude-Level,  for  use  with  Solar  Transit, 

see  page  82 6.00  .15 

195.  Jones’  Latitude  Arc,  with  reversible  level,  see 

page  83 73.00 

196.  Striding  or  Adjusting-Level,  see  page  86 3.00  .15 

• 

Note. — For  Tripods,  see  pages  176-179  and  267  and  268.  For 
Leather  Cases,  see  pages  180  and  269. 

SOLAR  COMPASS. 

210.  Burt’s  Solar  Compass,  with  leveling-screws  and  clamp  and 

tangent  to  spindle,  and  tripod,  see  page  99 $210.00 

Note. — For  Pocket  Solar  Compass,  see  No.  275,  and  pages  182  and  264. 


W.  &>  L.  E.  GURLEY,  TROY,  N.  Y.  263 

RAILROAD  COMPASSES. 

No.  Price. 

215.  Railroad  Compass,  two  verniers  to  limb,  limb  reading  to 

1 minute,  5-inch  needle,  brass  cover,  outkeeper  and 

staff  mountings 170.00 

216.  Railroad  Compass,  two  verniers  to  limb,  limb  reading  to 

1 minute,  5J-inch  needle,  brass  cover,  outkeeper  and 

staff  mountings,  see  page  104 75.00 

220.  Railroad  Compass,  one  vernier  to  limb,  limb  reading  to 
1 minute,  5J-inch  needle,  brass  cover,  outkeeper  and 
staff  mountings,  see  page  107 60.00 

These  Compasses  should  always  be  used  on  a tripod  when  practicable. 

Tripods  Nos.  415,  420  and  425  are  adapted  for  use  with  these  Compasses. 


VERNIER  COMPASSES. 


225.  Vernier  Compass,  4-inch  needle,  brass  cover,  outkeeper 

and  staff  mountings $30.00 

226.  Vernier  Compass,  5-inch  needle,  brass  cover,  outkeeper 

and  staff  mountings 35.00 

227.  Vernier  Compass,  6-inch  needle,  brass  cover,  outkeeper 

and  staff  mountings,  see  page  110 40.00 


PLAIN  COMPASSES. 


230.  Plain  Compass,  4-inch  needle,  brass  cover,  outkeeper  and 

staff  mountings $25.00 

231.  Plain  Compass,  5-inch  needle,  brass  cover,  outkeeper  and 

staff  mountings 30.00 

232.  Plain  Compass,  6 -inch  needle,  brass  cover,  outkeeper  and 

staff  mountings,  see  page  121 35.00 

Note. — Compasses  Nos.  210  to  232  are  packed  in  mahogany  case,  with 


lock  and  leather  strap.  A Compass  Tripod  (our  No.  415)  will  be  furnished 
with  any  of  these  Compasses,  Nos.  215-232,  at  an  extra  cost  of  $5.00 ; and  if 
the  staff  mountings  are  omitted  we  deduct  $2.00. 


ATTACHMENTS  AND  EXTRAS  FOR  COMPASSES. 

Price.  Post. 


240.  Compound  Tangent  Ball-Spindle,  see  page  122 $ 7.00  $0.30 

241.  Leveling- Adopter,  large  size,  see  page  122 7.00  .40 

242.  Leveling-Head  with  plates,  leveling-screws  and 

clamp  and  tangent,  fitted  to  use  with  tripods 
Nos.  401,  406,  411,  415,  420  and  425,  see 

page  123 13.00 

245.  Compass  Tripod  Mountings,  without  the  legs 4.00  .60 


Note. — For  Tripods,  see  pages  176-179  and  267  and  268.  For 
Leather  Cases,  see  pages  180  and  269. 


264  IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 

TELESCOPIC  SIGHT.  (Patented.) 

ATTACHABLE  TO  COMPASS  SIGHT.  See  pages  124-130. 

No.  Price.  Post. 

260.  Achromatic  Telescope,  9-inch,  power  about  12 

diameters - $15.00  $0.45 

261.  Achromatic  Telescope,  9-inch,  larger  object-glass, 

power  about  20  diameters,  see  page  124 17.00  .45 

262.  Achromatic  Telescope,  9-inch,  same  as  No.  261, 

and  with  stadia  wires 20.00  .50 

We  add  to  the  Telescope  Sight  the  following  extras, 
at  prices  named  : 

265.  Vertical  Circle,  with  vernier  to  5 minutes 5.00 

266.  Level  on  Telescope,  with  ground  and  graduated  vial  5.00 

267.  Clamp  and  Tangent  to  telescope  axis 5.00 

268.  Offset-standard  with  counterpoise,  to  bring  the  tele- 

scope over  the  line  of  zeros 7.50  .50 

POCKET  SOLAR  COMPASS. 

275.  Pocket  Solar  Compass,  one  vernier  to  limb,  limb  read- 

ing to  1 minute,  3-inch  needle,  with  two  levels, 
folding  sights  and  staff  mountings,  see  page  132.  ..$100.00 

276.  Pocket  Solar  Compass,  with  light  tripod 105.00 

277.  Pocket  Solar  Compass,  with  light  extension  tripod...  L10.00 

278.  Pocket  Solar  Compass,  with  light  extension  tripod 

and  leveling-head  with  clamp  and  tangent 120.00 

280.  Side  Telescope  and  Counterpoise  fitted  to  new 

Pocket  Solar  Compass 25.00 

POCKET  RAILROAD  COMPASSES. 

285.  Pocket  Railroad  Compass,  one  vernier  to  limb,  limb 
5 inches  diameter  reading  to  1 minute,  and  with 
clamp  and  tangent,  3J-inch  needle,  folding  sights, 

two  levels  and  staff  mountings,  see  page  135 $40.00 

288.  Pocket  Railroad  Compass,  one  vernier  to  limb  with 
clamp  and  tangent,  limb  inside  the  compass- 
circle  and  reading  to  1 minute,  4J-inch  needle, 

folding  sights,  two  levels  and  staff  mountings 33.00 

290.  Pocket  Railroad  Compass,  4J-inch  needle,  clamp 
and  tangent  to  limb,  limb  reading  to  1 minute, 
clamp  and  tangent  to  main  spindle  or  socket,  and 
fitted  with  our  Telescopic  Sight  No.  260,  with  the 
extras  of  level,  vertical  circle  to  5 minutes,  and 
clamp  and  tangent  to  telescope  axis,  and  with  tripod  73. 00 


IV.  &•  L.  E.  GURLEY,  TROY,  N.  Y.  265 

POCKET  RAILROAD  COMPASSES.—  Concluded. 

No.  Price.  Post. 

291.  Pocket  Railroad  Compass,  same  as  No.  290,  but 

with  Telescope  No.  261 $75.00 

292.  Pocket  Railroad  Compass,  same  as  No.  290,  but 

with  Telescope  No.  262 78.00 

293.  Pocket  Railroad  Compass,  same  as  No.  292,  and 

with  Leveling- Adopter,  complete  as  shown  on 
page  137 83.00 

POCKET  VERNIER  COMPASSES. 

300.  Pocket  Vernier  Compass,  3J-inch  needle,  folding 

sights,  two  levels  and  staff  mountings,  see  page  139  $16.00  $0. 70 
305.  Pocket  Vernier  Compass,  4J-inch  needle,  folding 

sights,  two  levels  and  staff  mountings,  seepage  139  18.00  1.10 

310.  Pocket  Vernier  Compass,  4J-inch  needle,  clamp  and 

tangent  to  main  spindle  or  socket,  and  fitted  with 
our  Telescopic  Sight  No.  260,  with  extras  of  level, 
vertical  circle  to  5 minutes  and  clamp  and  tangent 
to  telescope  axis,  and  with  tripod 58.00 

311.  Pocket  Vernier  Compass,  same  as  No.  310,  but  with 

Telescope  No.  261 60.00 

312.  Pocket  Vernier  Compass,  same  as  No.  310,  but  with 

Telescope  No.  262,  see  page  141 63.00 

POCKET  PLAIN  COMPASSES. 

315.  Pocket  Plain  Compass,  2J-inch  needle  and  folding 

sights $ 8.00  $0.25 

316.  Pocket  Plain  Compass,  2J-inch  needle,  folding  sights 

and  staff  mountings,  see  page  142 10.00  .35 

317.  Pocket  Plain  Compass,  3J-inch  needle  and  folding 

sights 10.00  .40 

318.  Pocket  Plain  Compass,  3J-inch  needle,  folding 

sights  and  staff  mountings,  see  page  142 12.00  .50 

319.  Pocket  Plain  Compass,  3J-inch  needle,  folding 

sights,  two  levels  and  staff  mountings 13.50  50 

EXTRAS  FOR  POCKET  COMPASSES. 

325.  Clamp  and  Tangent  fitted  to  ball-spindle  of  Com- 

passes Nos.  285,  288,  300,  305,  and  315  to  319..  $ 5.00 

326.  Rack  and  Pinion  to  variation  arc  of  Compasses  Nos. 

288  to  312 4.00 

327.  Leveling- Adopter,  small  size,  .see  page  142  5.00  $0.25 

328.  Leveling-Head  with  plates,  leveling-screws  and 

clamp  and  tangent  to  spindle 10.00 

"Note. — For  Tripods,  see  pages  176-179  and  268.  For  Leathfer 
Cases,  see  pages  180  and  269. 


266  IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 

GEOLOGISTS’  AND  CLINOMETER  COMPASSES. 

No.  Price.  Post. 

335.  Geologists’  Compass  (of  Aluminum),  graduated  mov- 
able sighting  circle,  graduated  base,  variation  arc, 
folding  sights,  two  levels,  clinometer  and  staff 

mountings,  see  page  143 $24.00  $0.35 

338.  Clinometer  Compass  (of  brass),  3J-inch  needle, 
folding  sights,  square  base,  two  levels,  clinometer 
and  staff  mountings,  see  page  144 16.00  .50 

A small  light  tripod  for  these  compasses  costs  extra  $5.00. 

MINERS’  COMPASSES  OR  DIPPING-NEEDLES. 

FOR  TRACING  VEINS  OF  MAGNETIC  IRON  ORE. 

340.  Miners’  Dip-Compass,  3-inch  needle  with  stop, 

glass  on  both  sides,  in  wood  case,  see  page  146...  $12.00  $0.25 

341.  Miners’  Dip-Compass,  3-inch  needle  with  stop, 

glass  on  both  sides,  with  brass  covers 12.00  .35 

344.  Miners’  Dip-Compass,  3-inch  Norwegian  needle 

with  stop,  glass  on  both  sides,  with  brass  covers, 

see  page  146 12.00  .35 

345.  Miners’  Dip-Compass,  4-inch  Norwegian  needle 

with  stop,  glass  on  both  sides,  with  brass  covers..  15.00  .50 

DIAL  COMPASSES. 

348.  Brass  Dial  Compass,  with  hour-circle*  graduated  for 

any  latitude  as  ordered,  variation  arc,  graduated 
base,  one  folding  sight,  two  levels  and  clinom- 
eter, see  page  148 $18.00  $0.40 

349.  Dial  Compass,  same  as  No.  348,  and  with  staff 

mountings  complete 20.50  .50 

350.  Aluminum  Dial  Compass,  with  hour-circle  graduated 

for  any  latitude  as  ordered,  graduated  base,  gradu- 
ated movable  sighting  circle,  variation  arc,  one 
folding  sight,  one  removable  sight,  two  levels, 

clinometer  and  staff  mountings,  see  page  150 30.00  .45 

Extra  Hour-Circles,  graduated  for  any  latitude  as 
ordered,  to  fit  either  of  these  Dial  Compasses, 
each 5.00  .12 

A light  tripod  for  the  Dial  Compasses  Nos.  349  and  350  costs  extra 
$5.00. 


LEVELING-INSTRUMENTS 


ENGINEERS’  Y-LEVELS. 

No.  Price. 

375.  Y-Level,  22-inch  telescope,  with  leveling-screws,  clamp 

and  tangent  and  tripod |115.00 

376.  Y-Level,  20-inch  telescope,  with  leveling-screws,  clamp 

and  tangent  and  tripod,  see  page  153 110.00 

377.  Y-Level,  18-inch  telescope,  with  leveling-screws,  clamp 

and  tangent  and  tripod 110.00 

378.  Y-Level,  15-inch  telescope,  with  leveling-screws,  clamp 

and  tangent  and  tripod,  see  page  166 90.00 

ARCHITECTS’  Y-LEVELS. 

380.  Architects’  Level,  12-inch  telescope,  with  leveling-screws 

and  tripod,  see  page  167 $50.00 

381.  Architects’  Level,  12-inch  telescope,  with  leveling-screws, 

clamp  and  tangent  and  tripod,  see  page  168 65.00 

Note. — A compass,  without  sights  and  with  3-inch  needle,  can  be  attached 
to  the  telescopes  of  these  leveling-instruments,  Nos.  375  to  381,  and  used  to 
obtain  the  bearing  of  lines  when  desired  ; its  extra  cost  is  $10.00.  Stadia  wires 
are  furnished  with  any  of  our  Y-Levels,  free  of  charge,  if  requested  when  the 
instrument  is  ordered. 

DRAINAGE  LEVELS. 

385.  Drainage  Level,  with  staff  mountings $15.00 

386.  Drainage  Level,  with  staff  mountings  and  tripod 20.00 

387.  Drainage  Level,  with  staff  mountings,  leveling-screws  and 

tripod,  see  page  172 25.00 

388.  Drainage  Level,  same  as  No.  387,  and  with  compass 

attached,  see  page  173 30.00 

Note. — All  our  Levels,  Nos.  375  to  388,  are  packed  in  mahogany  case  with 
lock,  and  strap  or  handle.  For  Level  Tripods,  see  pages  176-179  and  268. 

For  Leather  Cases,  see  pages  180  and  269. 

TRANSIT  TRIPODS. 

400.  Plain  Tripod  for  Transits  Nos.  1 to  90,  see  page  177 $10.00 

401.  Plain  Tripod  for  Transits  Nos.  100  to  117 5.00 

405.  Split-Leg  Tripod  for  Transits  Nos.  1 to  90,  see  page  178..  12.00 

406.  Split-Leg  Tripod  for  Transits  Nos.  100  to  117 10.00 

410.  Extension  Tripod  for  Transits  Nos.  1 to  90,  see  page  179..  15.00 

411.  Extension  Tripod  for  Transits  Nos.  100  to  117...... 12.00 

267 


268  IV.  L.  E.  GL'RLEY,  TROY,  X.  Y. 

COMPASS  TRIPODS. 

No.  Price. 

415.  Plain  Tripod  for  Compasses  Nos.  210  to  232,  see  page  177..  $5.00 

416.  Plain  Tripod  for  Pocket-Compasses  Nos.  275  to  319 5.00 

420.  Split-Leg  Tripod  for  Compasses  Nos.  210  to  232 10.00 

421.  Split-Leg  Tripod  for  Pocket-Compasses  Nos.  275  to  319...  8.00 

425.  Extension  Tripod  for  Compasses  Nos.  210  to  232 12.00 

426.  Extension  Tripod  for  Pocket-Compasses  Nos.  275  to  319..  10.00 


LEVEL  TRIPODS. 

430.  Plain  Tripod  for  Levels  Nos.  375  to  378,  see  page  177...  $10.00 

431.  Plain  Tripod  for  Levels  Nos.  380  to  388 5.00 

435.  Split- Leg  Tripod  for  Levels  Nos.  375  to  378,  see  page  178  12.00 

436.  Split-Leg  Tripod  for  Levels  Nos.  380  to  388 10.00 

440.  Extension  Tripod  for  Levels  Nos.  375  to  378,  see  page  179  15.00 

441.  Extension  Tripod  for  Levels  Nos.  380  and  381 12.00 

442.  Extension  Tripod  for  Levels  Nos.  385  to  388 10.00 


BRASS  PLUMMETS.  Plain. 


NO.  465. 


No. 

Price. 

Post. 

450. 

Plummet,  screw  head. 

steel 

point,  6 oz 

$1.00 

$0.15 

452. 

Plummet,  screw  head. 

steel 

point,  10  oz 

1.50 

.20 

454. 

Plummet,  screw  head. 

steel 

point,  16  oz 

2.00 

.25 

456. 

Plummet,  screw  head. 

steel 

point,  24  oz 

2.75 

.35 

458. 

Plummet,  screw  head. 

steel 

point,  32  oz 

3.50 

.45 

460. 

Plummet,  screw  head. 

steel 

point,  long  neck,  12  oz 

2.00 

.25 

BRASS  PLUMMETS. 

Adjustable. 

These  Plummets  have  a concealed  reel,  R, 
around  which  the  string  is  wound  by  turning  the 
milled  head,  K.  oh  top.  The  friction  upon  the  reel 
will  hold  the  Plummet  at  any  desired  point  of 
the  line. 

465.  Adjustable  Plummet,  10  oz $2.50  $0.20 

469.  Adjustable  Plummet,  30  oz — 5.00  .45 


269 


W.  6-  Z.  E.  GURLEY,  TROY,  N.  Y. 

SOLE -LEATHER  CASES. 

No  TO  FIT  OUTSIDE  THE  WOOD  BOX.  Price 

475.  Leather  Case  and  Strap,  for  Engineers’  or  Sur- 

veyors’ Transits,  price  according  to  size $8.00  to  $10.00 

476.  Leather  Case  and  Strap,  for  Mountain,  Reconnois- 

sance  or  Builders’  Transits 8.00 

477.  Leather  Case  and  Strap, for  large  Solar  Compasses..  10.00 

478.  Leather  Case  and  Strap,  for  Surveyors’  Compasses, 

Nos.  215  to  232,  price  according  to  size 7.00  to  9.00 

479.  Leather  Case  and  Strap,  for  Engineers’  Y-Levels, 

price  according  to  size 8.00  to  10.00 

480.  Leather  Case  and  Strap,  for  Architects’  Level 7.00 

481.  Leather  Case  and  Strap,  for  Drainage  Level 4.00 

Leather  Case  and  Shoulder-Strap  for  Pocket - 

Compasses,  sizes  as  follows : n ~ 

Price.  Post. 

485.  Size  for  Compasses  Nos.  315,  316,  335,  340  to  344, 

348  to  350 $2.50  $0.20 

486.  Size  for  Compasses  Nos.  300,  317  to  319,  338,  345,  3.00  .30 

487.  Size  for  Compasses  Nos.  275,  285,  288,  305. 4.00  .50 

488.  Size  for  Compasses  Nos.  290  to  293,  310  to  312 6.00 

Leather  Pouch  and  Shoulder-Strap,  fitted  to 
receive  Pocket- Compasses  without  wood  box,  sizes  as 
follows : 


490.  Size  for  Compasses  Nos.  315,  316,  335,  340  to  344, 

348  to  350 $2.00  $0.15 

491.  Size  for  Compasses  Nos.  300,  317  to  319,  338,  345..  2.50  .25 

492.  Size  for  Compasses  Nos.  288,  305 3.00  .35 

Note. — We  are  prepared  to  make  to  order  Leather  Cases  and 
Pouches  of  any  style  and  size  that  may  be  desired.  See  page  180. 


270 


W.  &>  L.  E.  GURLEY,  TROY,  N.  Y. 


LEVELING-RODS.  (See  pages  181-190 .) 

No.  Price. 

500.  Philadelphia  Rod,  7t3q  feet  closed,  sliding  to  13  feet $14.00 

502.  Philadelphia  Mining  Rod,  3^  feet  closed,  sliding  to  5 feet  12.00 

503.  Boston  Rod,  6 feet  closed,  sliding  to  11  feet 14.00 

504.  Troy  Rod,  6J  feet  closed,  sliding  to  12  feet 10.00 

505.  New  York  Rod,  2 ply,  6t8q  feet  closed,  sliding  to  12  feet...  14.00 

507.  New  York  Rod,  3 ply,  5 feet  closed,  sliding  to  12J  feet...  18.00 

508.  New  York  Rod,  4 ply,  5 feet  closed,  sliding  to  16  feet 20.00 

509.  New  York  Mining  Rod,  2 ply,  3T^  feet  closed,  sliding  to 

5t%  feet 12.00 

510.  Architects’  Rod,  5J  feet  closed,  sliding  to  10  feet,  in  inches 

and  16ths 6.00 

511.  Architects’  Rod,  5 J feet  closed,  sliding  to  10  feet,  in  feet 

and  lOOths 6.00 

512.  Machinists’  Rod,  6J  feet  long,  with  swivel  hook  for  shafting  5.00 

513.  Telemeter,  or  Stadia  Rod,  6 feet  folded,  unfolding  to  12  feet  12.00 

514.  Telemeter,  or  Stadia  Rod,  7 feet  folded,  unfolding  to  14  feet  13.00 

515.  Telescopic  Rod,  3 ply,  5 feet  closed,  sliding  to  14  feet 22.00 

516.  Cross-Section  Rod,  10  feet  long,  with  level-vial  at  each  end  10.00 

518.  Plain  Rod,  without  target,  10  feet  long,  feet  and  lOOths...  6.00 

519.  Plain  Rod,  without  target,  12  feet  long,  feet  and  lOOths...  7.00 

520.  Plain  Rod,  without  target,  14  feet  long,  feet  and  lOOths...  8.00 

521.  Plain  Rod,  without  target,  16  feet  long,  feet  and  lOOths...  9.00 


Note. — Plain  Rods,  Nos.  518  to  521,  if  made  with  a hinge  joint  at  the  center,  fold- 
ing once,  cost  $2.00  each  extra.  Any  of  our  Leveling-Rods  made  with  metric  graduations 
without  extra  charge. 

FLEXIBLE  OR  POCKET  LEVELING-RODS. 


Price.  Post. 


525.  Pocket  Leveling-Rod,  10  feet  long,  self-reading  to 

feet  and  lOOths,  made  of  prepared  canvas,  can  be 
coiled  up  and  carried  in  pocket ; in  use  it  is 
fastened  to  a board  with  thumb  tacks $3.25  $0.25 

526.  Pocket  Leveling-Rod,  same  as  No.  525,  12  feet 

long 4.00  .30 

527.  Pocket  Leveling-Rod,  same  as  No.  525,  14  feet 

long 4.50  .30 

528.  Pocket  Leveling-Rod,  same  as  No.  525,  3J  meters 

long,  divided  to  centimeters 4.00  .30 


TV.  &•  L.  E.  GURLEY ; TROY,  N.  V. 


271 


COMBINED  LEVELING-POLE  AND  FLAGSTAFF. 

No.  Price. 

530.  Wood  Leveling- Pole  and  Staff,  7 feet  long,  see  page  191...  $5.00 

531.  Wood  Leveling-Pole  and  Staff,  9 feet  long 6.00 

WOOD  AND  IRON  FLAGSTAFFS.  (See page  igi) 

These  staffs  are  divided  in  feet,  which  -are  painted  alternately 
red  and  white. 

534.  Wood  Staff,  6 feet  long,  with  metal  shoe $2.00 

535.  Wood  Staff,  8 feet  long,  with  metal  shoe 2.25 

536.  Wood  Staff,  10  feet  long,  with  metal  shoe 2.50 

539.  Aligning  or  Ranging-Pole,  6 feet  long,  hung  in  gimbals...  4.00 

Note. — This  pole  consists  of  an  iron  tube,  of  an  inch  diameter,  6 feet 
long,  and  being  hung  in  gimbals  always  assumes  a vertical  position. 

541.  Iron  Tubular  Ranging- Pole,  6 feet  long,  inch  diameter  2.75 

543.  Iron  Tubular  Ranging-Pole,  8 feet  long,  inch  diameter  3.00 

544.  Iron  Tubular  Ranging-Pole,  10  feet  long,  i-|  inch  diameter  3.50 

Note. — Any  of  the  above  staffs  with  metric  graduations  (five  to  a meter) 
at  same  price. 

f Price.  Post. 

545.  Rod-Level,  for  plumbing  a Rod  or  Staff,  see  page 

192 $3.00  $0.15 

546.  Circular  Rod-Level,  with  folding  joint,  see  page  192  3.00  .15 


272  IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 

PLANE-TABLE  OUTFITS. 

No.  Price. 

549.  Plane-Table,  with  board  30x24  inches,  mounted  on  large 

tripod  with  leveling- socket  and  clamp,  and  with  plumb- 
ing-arm, plummet  and  clamps  for  paper $45.00 

Set  of  three  leveling-screws 10.00 

Clamp  and  tangent,  for  orienting 10.00 

Combined  Compass  with  levels  and  square  base 15.00 

Alidade  with  telescope  11  inches  long,  with  stadia,  4J- 
inch  vertical  circle  to  J minute,  level  on  telescope  and 
clamp  and  tangent,  on  column,  power  of  telescope  24 
diameters,  see  page  201,  No.  583 90.00 

Total,  as  shown  on  page  196 $170.00 

550.  Plane-Table,  with  board,  tripod,  etc.,  as  in  No.  549 $45.00 

Combined  Compass  with  levels  and  square  base 15.00 

Alidade  with  telescope  11  inches  long,  with  stadia,  • 

4J-inch  vertical  circle  to  1 minute,  level  on  telescope 
and  clamp  and  tangent,  on  column,  power  of  telescope 
24  diameters,  see  page  201,  No.  583 90.00 

Total $150.00 

553.  Plane:Table,  with  board,  tripod,  etc.,  as  in  No.  549 $45.00 

Combined  Compass  with  levels  and  square  base 15.00 

Alidade  with  telescope  9 inches  long,  power  20  diameters, 
with  stadia,  vertical  circle  to  1 minute,  level  on  tele- 
scope and  clamp  and  tangent,  on  column,  see  pages 
193  and  201,  No.  582 70.00 

Total,  as  shown  on  page  193 $130.00 

556.  Plane-Table  with  board,  tripod,  etc.,  as  in  No.  549 $45.00 

Combined  Compass  with  levels  and  square  base 15.00 

Alidade  with  telescopic  sight  No.  262,  with  stadia,  vertical 
circle  to  5 minutes,  level  and  clamp  and  tangent,  see 
page  200,  No.  581 , 50.00 

Total $110.00 

559.  Plane-Table,  with  board,  tripod,  etc.,  as  in  No.  549 $45.00 

Combined  Compass  with  levels  and  square  base 15.00 

Alidade  with  sight- vanes,  see  page  200,  No.  580 15.00 

Total $75.00 

560.  Plane-Table,  with  board,  tripod,  etc.,  as  in  No.  549,  and 

omitting  Compass  and  Alidade $45.00 

563.  Set  of  three  leveling- screws  for  Plane-Tables  Nos.  550-560, 

extra 10.00 

564.  Clamp  and  tangent,  for  orienting,  for  Plane-Tables  Nos. 

550-560,  extra 10.00 


W.  L.  E.  GURLEY,  TROY,  N.  Y.  273 

JOHNSON'S  IMPROVED  PLANE-TABLE 
AND  EXTRAS. 

(Prices  for  separate  parts.  See  engraving,  page  199.) 

No.  Price. 

570.  Johnson’s  Plane-Table  Movement  and  plain  tripod $45.00 

(If  tripod  has  extension  legs,  the  extra  cost  is  $5.00.) 

573.  Drawing  Board,  31x24  inches,  with  brass  screw-plate 

fitted,  and  with  eight  clamp-screws  and  sockets  for 
paper 5.00 

574.  Plumbing-arm  and  plummet 4.00 

575.  Combined  Compass  with  levels  and  square  base 15.00 

JOHNSON’S  PLANE-TABLE  OUTFITS. 

576.  Johnson’ s Plane-Table  Movement  and  tripod,  with  drawing- 

board,  31x24  inches,  with  brass  screw-plate  fitted  and 

with  eight  clamp-screws  and  sockets  for  paper $50.00 

Plumbing- arm  and  plummet 4.00 

Combined  Compass  with  levels  and  square  base 15,00 

Alidade  with  telescope  11  inches  long,  with  stadia,  4J^-inch 
vertical  circle  to  1 minute,  level  on  telescope  and  clamp 
and  tangent,  on  column,  power  of  telescope  24  diameters, 
see  page  201,  No.  583 90.00 

Total,  as  shown  on  page  199 $159.00 

577.  Plane-Table,  with  tripod,  board,  etc.,  as  in  No.  576 $50.00 

Plumbing-arm  and  plummet 4.00 

Combined  Compass  with  levels  and  square  base 15.00 

Alidade  with  telescope  9 inches  long,  power  20  diameters, 

with  stadia,  vertical  circle  to  1 minute,  level  on  telescope 

and  clamp  and  tangent,  on  column,  No.  582 70.00 

Total $139.00 

578.  Plane-Table,  with  tripod,  board,  etc.,  as  in  No.  576 $50.00 

Plumbing-arm  and  plummet 4. 00 

Combined  Compass  with  levels  and  square  base 15.00 

Alidade  with  telescopic  sight  No.  262,  with  stadia,  verti- 
cal circle  to  5 minutes,  level  and  clamp  and  tangent, 

see  page  200,  No.  581  50.00 

Total  $119.00 

579.  Plane-Table,  with  tripod,  board,  etc.,  as  in  No.  576. $50.00 

Plumbing- arm  and  plummet 4. 00 

Combined  Compass  with  levels  and  square  base 15.00 

Alidade  with  sight-vanes,  see  page  200,  No.  580 15.00 

Total $84.00 


274  IV.  &■  L.  E.  GURLEY,  TROY,  N.  Y. 

ALIDADES. 

No.  Price. 

580.  Alidade  with  Compass-sights,  see  page  200  $15.00 

581.  Alidade  with  telescopic  sight  No.  262,  with  stadia,  ver- 

tical circle  to  5 minutes,  level  and  clamp  and  tangent, 

see  page  200 £» 50.00 

582.  Alidade  with  telescope  9 inches  long,  power  20  diam- 

eters, with  stadia,  vertical  circle  to  1 minute,  level  on 
telescope  and  clamp  and  tangent,  on  column  as  in 
engraving,  see  pages  193  and  201 70.00 

583.  Alidade  with  telescope  11  inches  long,  with  stadia, 

4J-inch  vertical  circle  to  1 minute,  level  on  telescope 
and  clamp  and  tangent,  on  column,  power  of  telescope 
24  diameters,  see  page  201 90.00 

584.  Alidade  with  telescope  11  inches  long,  stadia,  vertical  arc 

to  1 minute,  detachable  striding  level,  axis  tangent, 
diagonal  prism  for  eyepiece.  The  telescope  has  a power 
of  24  diameters,  and  is  made  erecting  or  inverting,  as 
ordered,  and  is  mounted  on  column,  see  page  202 118.00 

Note. — The  Alidades  as  above  described  can  be  used  with  any  of  our 
Plane-Tables  Nos.  549-579,  and  will  be  sold  separately  at  the  prices  named. 

TRAVERSE  PLANE-TABLE  — U.  S.  G.  S.  PATTERN. 

586.  Traverse-Table  Board,  15  x 15  inches,  with  Box  Compass 

let  into  one  edge,  Ruler-Alidade  with  graduated  edge 
and  folding  sights,  and  with  tripod,  complete  as  shown 
on  page  203 $25.00 

If  the  tripod  has  extension  legs,  add  extra  $5.00. 

When  desired,  we  furnish  separate  parts  of  this  Plane-Table 
at  the  following  prices  : 

587.  Drawing-Board  with  brass  screw-plate,  and  with  tripod 

head  and  plain  legs 9.00 

588.  Box-Compass,  rectangular  metal  case,  3-inch  needle 8.00 

589.  Ruler-Alidade,  10  inches  long,  with  graduated  edge  and 

folding  Sights 10.00 

590.  Pocket  Alidade,  6 inches  long,  with  graduated  edge  and 

folding  sights 7.50 

591.  Pocket  Alidade,  7 inches  long,  with  graduated  edge,  one 

peep  sight  and  one  folding  sight 12.00 


IV.  &•  L.  E.  GURLEY,  TROY,  N.  Y 


275 


BATSON  SKETCHING-CASE. 

No.  Price. 

595.  Batson  Sketching-Case,  as  shown  and  with  leather  case, 

see  pages  205-209... $30.00 

Wooden  Staff,  about  2 feet  long,  with  steel-pointed  shoe, 

extra 1.00 

Plain  Tripod,  about  3J  feet  long,  extra 3.50 


CURRENT-METERS. 

W.  G.  price’s  patent. 

For  measuring  the  velocity  of  the  current  of  rivers  and  harbors, 

at  any  depth. 

600.  Current-Meter  for  Harbors  and  Rivers,  see  page  212 

604.  Brass  Tubing,  graduated  to  feet  and  tenths,  and  jointed  in 

4-ft.  lengths,  per  length 

606.  Lead  Weight,  60  lbs.,  with  connections,  see  page  212 

609.  Electric  Register,  see  pages  212  and  216 

610.  Dry  Cell  Battery  of  three  cells,  inbox  with  lock  and  strap 
612.  Wet  Cell  Battery  of  three  cells,  in  box  with  lock  and  strap 
614.  Insulated  Copper  Wire  for  battery  (for  use  with  Meter  No. 

600),  per  foot 

616.  Acoustic  Current- Meter  for  small  streams,  see  page  219... 

617.  Electric  Current- Meter  for  small  streams,  complete  with 

electric  sounder,  cable  and  weight,  see  page  222 

(Extra  length  of  cable,  per  foot  10  cts. ) 

619.  Time-Recorder,  open  face,  nickel  case,  stem-winder,  with 

fly -back  attachment  for  starting  and  stopping.  Register- 
ing minutes,  seconds,  and  fifths  of  seconds 

620.  Boyden’s  Hook-Gauge,  see  page  225 

Note. — Water-Registers,  Tide-Gauges,  and  similar  instruments  made  to 


order  from  designs  submitted. 

HAND-LEVELS. 

Price.  Post. 

625.  Monocular  Hand-Level,  in  case,  see  page  228 $12.00  $0.20 

627.  Binocular  Hand-Level,  in  case,  see  page  228 15.00  .35 

630.  Locke’s  Hand-Level,  nickel-plated,  in  case,  see 

page  230 8.00  .20 

634.  Abney  Level,  an  improved  “ Locke’s  Hand-Level,” 
giving  angles  of  elevation  ; also  graduated  for 
slopes,  as  1 to  1,  2 to  1,  etc.;  in  case,  see  page 

231 13.50  .25 

636.  Abney  Level,  same  as  No.  634,  with  compass  and 

plain  staff  socket  attached ,18.00  .30 

Note. — Nos.  625  to  634  are  our  own  make ; No.  636  is  of  foreign  make. 


$100.00 

5.00 

15.00 

50.00 

4.00 

7.00 

.03 

50.00 

70.00 


6.00 

25.00 


276 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 

CHAINS.  (See pages  233-286.) 

No.  Prick.  Post, 

650.  33  feet,  50  links,  oval  rings,  No.  10  refined  iron  wire  $2.25  $0.65 

651.  33  feet,  50  links,  oval  rings,  No.  8 refined  iron  wire  2.50  .85 

652.  66  feet,  100  links,  oval  rings,  No.  10  refined  iron  wire  3.50  1.15 

653.  66  feet,  100  links,  oval  rings,  No.  8 refined  iron  wire  4.00  1.75 

656.  33  feet,  50  links,  oval  rings,  No.  10  best  steel  wire  4.00  .65 

658.  50  feet,  50  links,  oval  rings,  No.  10  best  steel  wire  4.75  .80 

659.  50  feet,  50  links,  oval  rings,  No.  8 best  steel  wire  5.50  .90 

660.  66  feet,  100  links,  oval  rings,  No.  10  best  steel  wire  7.00  1.15 

662.  100  feet,  100  links,  oval  rings,  No.  10  best  steel  wire  8.50  1.50 

663.  100  feet,  100  links,  oval  rings,  No.  8 best  steel  wire  10.00  1.80 

BRAZED  STEEL  CHAINS. 

670.  33  feet,  50  links,  No.  12  tempered  steel  wire,  brazed 

links  and  rings $ 5.00  $0.45 

671.  50  feet,  50  links,  No.  12  tempered  steel  wire,  brazed 

links  and  rings 6.00  .55 

672.  66  feet,  100  links,  No.  12  tempered  steel  wire, 

brazed  links  and  rings 9.00  .70 

673.  100  feet,  100  links,  No.  12  tempered  steel  wire, 

brazed  links  and  rings 10.00  1.00 

Our  brazed  steel  chains  displace  the  ordinary  chains 
wherever  they  are  tried,  on  account  of  superior  lightness 
and  strength.  They  are  practically  the  only  chains  now 
used  in  railroad  construction. 

Chains  of  two  and  four  poles  with  40  and  80  links, 
same  price  as  chains  of  50  and  100  links. 

Steel  snaps  to  make  full  chains  into  “half  chains,” 
without  extra  charge,  if  ordered  with  the  chain. 

GRUMMAN  PATENT  STEEL  CHAINS. 

680.  33  feet,  50  links,  No.  15  tempered  steel  wire,  weight 


1 lb $ 5.00  $0.28 

681’.  50  feet,  100  links,  No.  15  tempered  steel  wire, 

weight  1J  lbs 6.00  .30 

682.  66  feet,  100  links,  No.  15  tempered  steel  wire, 

weight  1J  lbs 9.00  .35 

683.  100  feet,  200  links,  No.  15  tempered  steel  wire, 

weight  lbs 11.00  .50 

685.  50  feet,  100  links,  No.  18  tempered  steel  wire, 

with  spring-balance,  level  and  thermometer,  for 

very  accurate  measurements,  weight  14 J oz 15.00  .25 

688.  Spring-balance  with  handle  and  steel  snap,  to  use 

with  chains  Nos.  680  to  683 2.50  .15 


W.  & L.  E.  GURLEY,  TROY , N.  Y.  277 

VARA  CHAINS. 

No.  Price.  Post. 

690.  10  varas,  50  links,  oval  rings,  No.  10  refined  iron 

wire $ 2.25  $0.55 

691.  10  varas,  50  links,  oval  rings,  No.  8 refined  iron 

wire 2i50  .75 

694.  20  varas,  100  links,  oval  rings,  No.  10  refined  iron 

wire • 3.50  1.00 

695.  20  varas,  100  links,  oval  rings,  No.  8 refined  iron 

wire -. 4.00  1.65 

700.  10  varas,  50  links,  oval  rings,  No.  10  best  steel 

wire 4.00  .55 

704.  20  varas,  100  links,  oval  rings,  No.  10  best  steel 

wire 7.00  1.00 

708.  10  varas,  50  links,  oval  rings,  No.  12  tempered  steel 

wire,  brazed  links  and  rings 5.00  .35 

710.  20  varas,  100  links,  oval  rings,  No.  12  tempered 

steel  wire,  brazed  links  and  rings 9.00  .65 

METER  CHAINS. 

715.  10  meters,  50  links,  oval  rings,  No.  10  refined  iron 

wire $ 2.25  $0.65 

716.  10  meters,  50  links,  oval  rings,  No.  8 refined  iron 

wire 2.50  .85 

719.  20  meters,  100  links,  oval  rings,  No.  10  refined  iron 

wire 3.50  1.15 

720.  20  meters,  100  links,  oval  rings,  No.  8 refined  iron 

wire 4.00  1.75 

723.  10  meters,  50  links,  oval  rings,  No.  10  best  steel 

wire 4.00  .65 

727.  20  meters,  100  links,  oval  rings,  No.  10  best  steel 

wire 7.00  1.15 

730.  10  meters,  50  links,  oval  rings,  No.  12  tempered 

steel  wire,  brazed  links  and  rings  5.00  .45 

732.  20  meters,  100  links,  oval  rings,  No.  12  tempered 

steel  wire,  brazed  links  and  rings 9.00  .70 

MARKING-PINS  AND  TIMBER-SCRIBE. 

740.  Set  of  11  Pins,  No.  4 iron  wire,  14  inches  long $1.25  $0.50 

742.  Set  of  11  Pins,  No.  6 steel  wire,  14  inches  long 1.50  .40 

744.  Set  of  11  Pins,  No.  6 steel  wire  weighted,  14  inches 

long 2.50  1.25 

746.  Set  of  11  Pins,  No.  10  steel  wire,  9 inches  long,  in 

leather  pouch 2.00  .25 

748.  Set  of  11  Pins,  No.  4 brass  wire,  14  inches  long 2.50  .50 

750.  Timber -Scribe,  for  marking  trees,  posts  or  boards. ...  1.25  .15 


278 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y 


STEEL  RIBBON  CHAIN-TAPES. 

J INCH  WIDE,  AND  WITH  HANDLES  AND  REEL. 


No.  Price.  Post. 

760.  Steel  Ribbon,  33  feet,  graduated  each  link $3.50  $0.25 

761.  Steel  Ribbon,  50  feet,  graduated  each  foot 4.00  .30 

762.  Steel  Ribbon,  66  feet,  graduated  each  link 4.50  .35 

763.  Steel  Ribbon,  100  feet,  graduated  each  foot 5.00  .40 

765.  Steel  Ribbon,  200  feet,  graduated  each  foot  up  to 

100  feet,  and  the  last  100  feet  graduated  each  10 

feet 7.50  .70 

767.  Steel  Ribbon,  300  feet,  graduated  each  foot  up  to 
100  feet,  and  the  last  200  feet  graduated  each  10 
feet 10.00 


The  50,  100,  200  and  300  feet  Chain -tapes  also  have 
the  first  and  last  foot  in  lOths. 


STEEL  RIBBON  BRIDGE-TAPES. 

J INCH  WIDE,  WITH  HANDLES  AND  EXTRA  FINE  REELS. 


No.  Price. 

770.  Steel  Ribbon,  300  feet,  graduated  each  5 feet $13.00 

771.  Steel  Ribbon,  400  feet,  graduated  each  5 feet 15.00 

772.  Steel  Ribbon,  500  feet,  graduated  each  5 feet 17.00 


Our  Bridge-tapes  are  mounted  on  substantial  wooden  reels 
with  aluminum  and  brass  mountings  and  swivel  handle. 

These  tapes  have  the  first  and  last  5 feet  graduated  each  foot. 

Note. — We  can  also  furnish  tapes,  Nos.  760-772,  graduated  each  meter 
or  each  vara.  See  page  239. 


TV.  dr*  Z.  E.  GURLEY,  TROY,  N.  Y. 

CHESTERMAN’S  METALLIC  TAPES. 


279 


Made  of  linen  thread,  interwoven  with  fine  brass  wire.  They  are 
f-inch  wide,  and  in  leather  cases.  The  graduations  are  in  lOths  or  12ths 
of  a foot,  as  desired,  on  one  side  and  in  links  on  the  reverse  side. 


No. 

780. 

782. 

783. 
786. 


Metallic  Tape,  33  feet,  in  lOths  or  12ths,  and  links.. 

Metallic  Tape,  50  feet,  in  lOths  or  12ths,  and  links.. 

Metallic  Tape,  66  feet,  in  lOths  or  12ths,  and  links.. 

Metallic  Tape,  100  feet,  in  lOths  or  12ths,  and  links 


Price.  Post. 

$2.10  $0.18 

2.60  .20 

3.00  .25 

4.20  .30 


Note. — We  can  furnish  metallic  tapes  with  metric  or  vara  measure 
on  reverse  side,  instead  of  links,  at  an  extra  cost  of  one  cent  per  foot. 


METALLIC  TAPES  WITHOUT  CASES. 

These  tapes  can  be  put  into  the  leather  cases  when  the  original  tape  line 

is  worn  out. 


790. 

791. 

792. 
794. 


Metallic  Tape,  33  feet,  in  lOths  or  12ths,  and  links, 

without  case 

Metallic  Tape,  50  feet,  in  lOths  or  12ths,  and  links, 

without  case 

Metallic  Tape,  66  feet,  in  lOths  or  12ths,  and  links, 

without  case 

Metallic  Tape,  100  feet,  in  lOths  or  12ths,  and  links, 
without  case 


$1.10 

$0.12 

1.50 

.15 

1.80 

.18 

2.90 

.20 

280 


JV. 


L.  E.  GURLEY,  TROY,  N.  Y. 


STANDARD  AMERICAN  STEEL  TAPES. 

ALL  STEEL,  f-INCH  WIDE,  IN  LEATHER  CASES  ; THE  MOST  ACCURATE, 
DURABLE  AND  PORTABLE  MEASURES. 


No.  Price.  Post. 

800.  Steel  Tape,  25  feet,  in  lOths  or  12ths,  and  links § 3.75  $0.15 

801.  “ “ 33  feet,  “ “ “ * “ 4.30  .18 

802.  “ “ 50  feet,  “ “ “ 6.00  .20 

803.  “ “ 66  feet,  “ “ “ “ 7.60  .23 

804.  “ “ 75  feet,  “ “ “ “ 8.60  .25 

805.  “ “ 100  feet,  “ “ “ “ 10.60  .30 


THE  “STAR”  STEEL  TAPE. 

f-INCH  WIDE,  IN  NICKELED  BRASS  CASES. 


808.  Steel  Tape,  25  feet,  in  lOths  or  12ths,  and  links $3.00  $0.15 

809.  “ 33  feet,  “ “ “ “ 3.20  .18 

810.  “ “ 50  feet,  “ “ “ “ 3.60  .20 

811.  “ “ 66  feet,  “ “ “ “ 4.40  .25 

812.  “ “ 75  feet,  “ “ “ “ 4.80  .30 

813.  “ “ 100  feet,  “ “ “ “ 6.40  .35 

CHESTERMAN’S  ENGLISH  STEEL  TAPES. 

f-INCH  WIDE,  IN  LEATHER  CASES,  FOLDING  HANDLE. 

815.  Steel  Tape,  33  feet,  in  lOths  or  12ths,  and  links $ 5.20  $0.18 

816.  “ “ 50  feet,  “ “ “ “ 7.20  .20 

817.  “ “ 66  feet,  “ “ “ “ 9.20  .23 

819.  “ “ 100  feet,  “ “ “ “ 12.80  .30 


W.  & L.  E.  GURLEY,  TROY,  N.  Y 


281 


PAINE’S  AMERICAN  STEEL  TAPES. 


J-INCH  WIDE,  IN  LEATHER  CASES,  FOLDING  HANDLES. 


No. 

820. 

Steel  Tape,  33  feet,  in  lOths  or 

12ths,  and  links.. 

Price. 

...  | 4.40 

Post. 

^0.18 

821. 

“ “ 50  feet,  “ 

it  a a 

...  6.40 

.23 

822. 

“ “ 66  feet,  “ 

a a a 

...  8.00 

.28 

823. 

“ “ 75  feet,  “ 

4 4 4 4 4 4 

..  9.60 

.30 

824. 

“ “ 100  feet,  “ 

4 4 4 4 4 4 

..  12.00 

.35 

PAINE’S  AMERICAN  STEEL  TAPES. 


J-INCH  WIDE,  IN  METAL  CASES,  FOLDING  HANDLES. 


No. 

830. 

Steel  Tape,  25  feet,  in 

lOths 

or  12ths,  and  links... 

Price. 
..  $2.80 

Post. 

$0.15 

831. 

“ “ 33  feet, 

a 

a 

* i 

..  3.60 

.18 

832. 

“ “ 50  feet, 

i i 

it 

a a 

..  4.80 

.23 

833. 

“ “ 66  feet, 

a 

i i 

n a 

..  6.40 

.28 

834. 

“ “ 75  feet, 

t i 

a 

a ti 

..  8.00 

.30 

835. 

“ “ 100  feet, 

1 1 

i ( 

a a 

..  9.60 

.35 

Note. — Paine’s  Tapes  (50  to  100  feet)  are  detachable  from  their 
cases,  and  furnished  with  an  extra  handle  (No.  841),  and  can  be  used 
as  a chain-tape. 


EXTRAS  FOR  PAINE’S  STEEL.  TAPES. 


No. 

840. 

Compensating  Handles,  detachable,  with  graduated 

Price. 

Post. 

scale,  per  pair 

$2.40 

$0.12 

841. 

Plain  Finger-ring  Handles,  detachable,  each 

.40 

.02 

843. 

Pocket  Thermometers,  each 

.85 

.15 

844. 

Spring- Balance,  with  handle  and  snap 

2.50 

.15 

845. 

Spring-Balance  and  Level,  with  handle  and  snap 

4.00 

.15 

Note. — Tapes  Nos.  800  to  835  are  graduated  to  feet,  lOths  and 
lOOths  of  a foot,  or  to  feet,  inches  and  8ths  of  inches,  as  desired,  on 
one  side  and  in  links  on  the  reverse  side. 


Tapes  Nos.  800  to  835*  with  metric  or  vara  measure 
on  reverse  side  instead  of  links,  at  an  extra  cost  of  two 
and  one-half  cents  per  foot. 


282 


L.  E.  GURLEY,  TROY,  N.  Y 


W.  6° 

EXCELSIOR  STEEL  TAPES. 


J-INCH  WIDE,  ON  BRASS  FRAME  WITH  HANDLE. 


No.  Price.  Post. 

850.  Steel  Tape,  33  feet,  in  lOths  or  12ths,  and  links $ 5.00  $0.20 

851.  “ “ 50  feet,  “ “ “ “ 6.40  .25 

852.  “ “ 66  feet,  “ “ “ “ 8.00  .30 

853.  “ “ 100  feet,  “ “ “ “ 11.50  .40 

855.  “ “ 50  feet,  “ “ u meters...  7.65  .25 

858.  “ “ 100  feet,  “ “ “ ...  14.00  .40 


Note. — Tapes  Nos.  850  to  853  are  graduated  to  feet,  lOths  and  lOOths  of  a foot,  or 
to  feet,  inches  and  8ths  of  inches,  as  desired,  on  one  side  and  in  links  on  the  reverse  side. 
Tapes  Nos.  855  and  858  have  metric  measure  on  the  reverse  side  instead  of  links. 


METRIC  AND  VARA  TAPES. 

We  can  furnish  any  of  our  tapes,  Nos.  780-835  and  850-858,  with 
metric  or  vara  measure  only,  at  prices  for  regular  style  of  tapes  of  similar 
lengths  in  feet.  If  with  metric  or  vara  measure  on  reverse  side,  instead  of 
links,  the  extra  cost  will  be  as  stated  on  pages  279  and  281. 


NICKEL-PLATED  TAPES. 

When  desired,  we  will  nickel-plate  our  steel  tapes,  Nos.  800-835  and 
850-858,  to  protect  from  rust,  at  the  following  prices  : 

25  33  50  66  75 

Each  $0.90  0.90  1.35  1.55  1.55 


100  feet. 
1.75 


W.  & L.  E.  GURLEY,  TROY,  N.  Y 283 

POCKET  STEEL  TAPES. 

IN  GERMAN  SILVER  CASES,  WITH  SPRING  AND  STOP. 

No.  Price.  Post. 

860.  Pocket  Steel  Tape,  3 feet,  in  lOths  or  12ths'. $1.00  $0.11 

863.  “ “ “ 6 “ “ “ 1.40  .12 

866.  “ “ “ 12  “ “ “ 2.50  .15 

870.  Pocket  Steel  Tape,  6 feet,  in  lOths  one  side  and 

12ths  reverse  side 1.60  .12 

873.  Pocket  Steel  Tape,  12  feet,  in  lOths  one  side  and 

12ths  reverse  side 2.80  .15 

875.  Pocket  Steel  Tape,  3 feet,  in  lOths  or  12ths,  and 

meter 1.10  .11 

877.  Pocket  Steel  Tape,  6 feet,  in  lOths  or  12ths,  and 

meter 1.60  .12 

879.  Pocket  Steel  Tape,  12  feet,  in  lOths  or  12ths,  and 

meter 2.80  .15 


SUPPLEMENT 

TO 

Thirty-Sixth  Edition  of  Manual. 

April,  1002. 

The  prices  in  this  Catalogue  may  vary  from  time  to  time,  on  account 
of  fluctuations  in  Market  Rates. 

This  Price-List  supersedes  all  previous  editions,  and  has  been 
carefully  revised  and  enlarged. 

When  ordering  goods  always  state  what  edition  of  Manual,  and 
number  in  Catalogue. 


DRAWING-INSTRUMENTS. 

T'O  GUIDE  the  Surveyor  and  Engineer  in  the  selection 
^ of  Drawing-Instruments,  we  here  add  a detailed 
description,  with  illustrations  and  prices  of  the  separate 
pieces  and  cases  of  the  different  kinds  in  general  use. 

Those  we  shall  first  mention  are  of  Swiss  manufacture, 
of  the  finest  quality  and  finish,  and  are  made  of  the  best 
German  silver  and  English  steel. 

We  show  first  the  regular  patterns  and  then  those  with 
the  celebrated  pivot-joint. 

The  Alteneder  instruments  are  the  best  of  American 
manufacture,  and  are  equally  good  with  those  of  Swiss 
make. 

The  fine  German  silver  instruments,  of  German  make, 
are  the  best  of  their  kind. 


284 


IV.  6-  L.  E.  GURLEY,  TROY,  N.  Y 285 

The  instruments  before  mentioned  are  intended  for 
Engineers,  Architects,  Draftsmen,  Machinists  and  Students 
in  Technical  Schools. 

The  cheaper  German  silver,  brass  and  nickel-plated 
instruments  are  for  Common  School  use  and  elementary 
practice. 

Parties  wanting  special  cases  made  up,  can  select  the 
pieces,  and  we  will  make  cases  to  suit,  at  an  additional  cost 
of  from  $2  to  $10,  according  to  the  size  and  quality  of  the 
cases,  which  are  made  of  morocco,  rosewood,  or  mahogany. 

For  prices  of  regular  size  cases,  see  page  294. 

For  the  convenience  of  our  customers,  we  will  furnish 
any  articles  not  on  our  list,  but  described  in  the  catalogue 
of  any  American  manufacturer  or  dealer  in  mathematical 
instruments,  at  catalogue  prices. 


SPECIAL  NOTICE. 

TV /T  ANY  of  our  smaller  instruments,  such  as  drawing -instruments, 
pocket -compasses,  chains,  tapes,  small  packages  of  paper  and 
parts  of  large  instruments,  can  be  sent  by  mail  securely  packed,  and  at 
much  lower  rates  than  are  charged  by  Express  Companies.  Packages 
not  exceeding  four  pounds  in  weight  can  be  sent  in  this  way  within  the 
United  States,  Canada  and  Mexico  at  a cost  of  one  cent  per  ounce. 

In  all  cases  where  goods  are  to  be  sent  by  mail,  the  cash 
for  postage  as  well  as  for  the  goods  must  accompany  the 
order. 

The  postage  required  is  mentioned  in  the  second  column 
of  the  Price-List,  and  for  articles  worth  more  than  one 
dollar  the  amount  named  for  postage  includes  the  cost  of 
registry. 

All  articles  can  be  registered  at  an  extra  cost  of  eight  cents  for  each 
package  besides  regular  postage.  Packages  for  registry  should  not  exceed 
four  feet  in  length. 

We  are  not  responsible  for  goods  lost  or  injured  when 
sent  by  mail. 


286  IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 

SUPERIOR  SWISS  DRAWING-INSTRUMENTS. 

OF  GERMAN  SILVER,  EXTRA  FINE  FINISH. 


1000.  1003.  1005.  1008.  1010.  1011. 

No.  Price.  Post. 


No.  Price.  Post. 

1000.  Plain  Dividers,  3J-inch,  with  handle $1.50  $0.10 

1002.  Plain  Dividers,  4J-inch,  without  handle 1.50  .12 

1003.  Plain  Dividers,  5-inch,  without  handle 1.75  .12 

1005.  Hairspring  Dividers,  3 J-inch,  with  handle 2.25  .10 


1 


W.  <5r*  Z.  E.  GURLEY,  TROY,  N.  Y 

287 

No. 

Price. 

Post. 

1007. 

Hairspring  Dividers,  4J-inch,  without  handle 

|2.25 

$0.12 

1008. 

Hairspring  Dividers,  5-inch,  without  handle 

2. 50 

.12 

1010. 

Pocket  Dividers,  5-inch,  with  sheath 

2.50 

.12 

1011. 

Three-legged  Dividers,  6-inch,  for  spacing  off  three 

points 

4.00 

.13 

1013. 

Whole  and  Half  Dividers,  7J-inch 

3.50 

.15 

1015.  1016.  1017.  1019.  1024. 


1015.  Compasses,  3J-inch,  with  two  fixed  needle  points..  3.00  .10 

1016.  Compasses,  3J-inch,  with  fixed  needle  and  pen 

points  3.00  .10 


288 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 


No.  Price.  Post. 

1017.  Compasses,  3J-inch,  with  fixed  needle  and  pencil 

points  $3.00  $0.10 

1018.  Compasses,  3J-inch,  with  fixed  needle  point,  and 

pen  and  pencil  points 4.50  .12 

1019.  Compasses,  34-inch,  with  pen,  pencil  and  needle 

points  5.00  .12 

1020.  Spring  Bow-Compasses,  3J-inch,  with  long  handle, 

two  steel  points,  pencil  and  needle  points  and  two 

pen  points  for  ruling  parallel  lines 7.00  .13 

1022.  Compasses,  5J-inch,  with  fixed  needle  point,  pen 

and  pencil  points  and  lengthening  bar 5.50  .15 

1024.  Compasses,  6-inch,  with  pen,  pencil  and  needle 

points  and  lengthening  bar 6.50  .15 


1028. 


Folded. 


Drawn  out  for  small  circles. 


1029. 


1029. 


No. 

1026. 


1028. 

1029. 


1033. 

1034. 

1035. 

1039. 

1040. 

1041. 

1042. 

1046. 

1047. 

1048. 


W.  & L.  E.  GURLEY,  TROY,  N.  Y. 


Price. 

Compasses,  6J-inch,  with  joint  in  each  leg,  pen, 
pencil  and  needle  points,  dotting  - pen  and 

lengthening  bar $9.00 

Pocket-Compasses,  with  folding  points 8.75 

Pillar- Compasses,  with  handles,  pen,  pencil  and 
two  needle  points  which  can  be  drawn  out  and 
used  as  a small  bow-pen  and  bow-pencil 9.75 


1033. 


Steelspring  Bow-dividers,  with  ivory  handle,  3-inch  1.50 

Steelspring  Bow-pen,  with  ivory  handle,  3-inch 2.00 

Steelspring  Bow-pencil,  with  ivory  handle,  3-inch..  2.00 
Steelspring  Bow-dividers,  with  ivory  handle,  3 J-inch  2. 00 
Steelspring  Bow-dividers,  with  needle  point,  ivory 

handle,  3J-inch 2.50 

Steelspring  Bow-pen,  with  needle  point,  ivory 

handle,  3J-inch 2.50 

Steelspring  Bow-pencil,  with  needle  point,  ivory 

handle,  3J-inch 2.50 

Spring  Bow-pen,  with  adjusting- screw 2.00 

Spring  Bow-pen,  with  adjusting- screw  and  pencil 

point . 3.00 

Spring  Bow-pen,  with  adjustable  point,  for  small 

circles 3.00 

Spring  Bow-pen  and  pencil,  with  adjustable  point, 

for  small  circles 4. 00 


289 

Post. 

$0.18 

.12 

.14 


.10 

.10 

.10 

.10 

.10 

.10 

.10 

.10 

.10 

.10 

.10 


1049. 


290 


W.  &=  L.  E.  GURLEY,  TROY,  N.  Y. 


1046. 


1047.  1048. 

(For  prices,  see  page  289.) 


1049. 


W.  & L.  E.  GURLEY,  TROY,  N.  Y.  291 


1055.  1056.  1057.  1060.  1062.  1064.  1065. 


1055.  1056.  1057.  1060.  1062.  1064.  1065. 

No.  Price.  Post. 

1055.  Drawing  -Pen*  with  joint  and  pin,  ivory  handle, 

4|-inch $1.25  $0.10 

1056.  Drawing-Pen,  with  joint  and  pin,  ivory  handle, 

5 J -inch 1.40  .10 

1057.  Drawing-Pen,  with  joint  and  pin,  ivory  handle, 

6J-inch 1.60  .10 

1060.  Railroad  Pen,  without  joints,  ivory  handle,  6-inch..  2.50  .10 


292 


IV.  &•  L.  E.  GURLEY \ TROY,  N.  K 


No.  Price.  Post. 

1062.  Railroad  Pen,  with  joints  in  blades  and  shanks,  im- 
proved pattern,  ivory  handle,  5J-inch $3.00  $0.10 

1064.  Dotting-Pen,  one  wheel,  ivory  handle,  6 inch 1.85  .10 

1065.  Dotting-Pen,  six  wheels,  improved  pattern,  with  ink 

reservoir,  ivory  handle,  6 -inch 3.50  .10 


1067. 


1067.  Beam-Compass  Furniture,  with  two  steel  points, 

pen,  pencil  and  needle  points,  in  morocco  case...  8.00  .20 

1068.  Beam-Compass  Furniture,  with  micrometer  adjust- 

ment, two  steel  points,  pen,  pencil  and  needle 
points,  and  wheel  attachment  to  stand  alone  ; all 
in  morocco  case 13.00  .30 

1069.  Hardwood  Bars  for  No.  1067  Beam-Compass 

24  30  36  48  inches  long. 

Each,  $0.25  $0.30  $0.35  $0.50 

Postage,  .10  .12  .15  .20  . 

1070.  Beam-Compasses,  18-inch,  in  two  German  silver 

bars,  with  two  steel  points,  pen,  pencil  and  needle 


points 10.50  .20 

1071.  Beam-Compasses,  24- inch,  three  bars,  with  two  steel 

points,  pen,  pencil  and  needle  points.... 11.75  .25 

1072.  Beam- Compasses,  36-inch,  three  bars,  with  two  steel 

points,  pen,  pencil  and  needle  points.... 15.25  30 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 


293 


No.  Price.  Post. 

1074.  Proportional  Dividers,  7J-inch,  divided  for  lines $8.00  $0.15 

1075.  Proportional  Dividers,  7J-inch,  divided  for  lines 

and  circles.. 9.00  .15 


294 


W.  &>  L.  E.  GURLEY,  TROY,  N.  Y. 


No.  Price.  Post. 

1076.  Proportional  Dividers,  8f-inch,  divided  for  lines 

and  circles,  and  with  rack  and  pinion  movement..$12.00  $0.18 

1078.  Proportional  Dividers,  9-inch,  divided  for  lines  and 

circles,  and  with  micrometer  screw 14.00  .20 

1079.  Proportional  Dividers,  9-inch,  divided  for  lines, 

circles,  planes  and  solids,  and  with  micrometer 

screw 16.00  .20 

Morocco  Cases  for  Proportional  Dividers  : 

To  fit  Dividers  Nos.  1074,  1075 80  .10 

“ “ No.  1076 1.10  .12 

“ “ Nos.  1078,  1079 1.20  .15 

1084.  Polar  Planimeter,  German  silver,  best  quality,  in 

morocco  case,  with  printed  directions 16.50  .25 

This  Planimeter  indicates  up  to  10  square  inches.  # 

1086.  Polar  Planimeter,  German  silver,  best  quality,  in 

morocco  case,  with  printed  directions 19.00  .25 

This  Planimeter  indicates  up  to  100  square  inches. 

1088.  Polar  Planimeter,  German  silver,  best  quality,  in 

morocco  case,  with  printed  directions ..  28.50  .35 


This  Planimeter  indicates  square  inches,  square  feet  and  square 
centimeters. 

1090.  Polar  Planimeter,  German  silver,  with  the  tracer- 
arm  graduated  nearly  its  entire  length  and  with 
vernier.  Easily  adjusted  to  any  desired  scale.  In 

mahogany  box,  with  printed  directions 33.00  .50 

By  means  of  the  Polar  Planimeter  a person  may  ascertain  the  area  of 
any  planimetrical  figure  more  correctly  and  in  less  time  than  the  most  ex- 
perienced Mathematician  could  calculate  it. 

Note. — The  Planimeters  mentioned  above  are  the  favorite  styles  and  the  best 
quality. 

We  can  furnish  cheaper  Planimeters  (to  order  only),  but  do  not  keep  them  in  stock. 

EMPTY  CASES  FOR  DRAWING-INSTRUMENTS, 

WITH  TRAY  FITTED  COMPLETE,  AND  WITH  LOCK.  SPACE  UNDER 

TRAY  FOR  SUNDRIES. 

Mahogany  Cases  Fitted,  Morocco  Cases  Fitted, 

with  Tray.  without  Tray. 


No. 

Size. 

Plain. 

Polished. 

Postage. 

Price. 

Postage. 

1092... 

..  8 

X 

3J  inches. 

|2.50 

$3.25 

$0.20 

$2.25 

$0.15 

1093... 

..  8 

X 

4 inches. 

2.75 

3.50 

.20 

2.50 

.15 

1094.... 

..  8 

X 

5 inches. 

3.00 

3.75 

.25 

2.75 

.18 

1095... 

..  9 

X 

5 inches. 

3.25 

4.00 

.30 

3.00 

.18 

1096... 

..  10 

X 

6 inches. 

4.00 

5.00 

.35 

4.00 

.20 

1097.... 

. 11 

X 

7 inches. 

4.75 

6.00 

.50 

4.50 

.25 

1098.... 

..  13 

X 

7 inches. 

5.75 

7.00 

.75 

5.00 

.50 

Other  sizes  made  to  order. 


(See  page  294.) 


1088. 


296 


W.  & L.  E.  GURLEY,  TROY,  N.  Y. 


SETS  OF  EXTRA  FINE  SWISS  DRAWING- 
INSTRUMENTS  IN  CASES. 


No.  Price.  Post. 

1100.  Morocco  Case,  containing  : 

Hairspring  Dividers,  No.  1005  ; Compasses,  No. 

1019  ; Bow-pen,  No.  1034  ; Drawing-Pen,  No. 

1055;  Box  of  Leads f>13.00  $0.15 

1102.  Morocco  Case,  containing  : 

Hairspring  Dividers,  No.  1008  ; Compasses,  No. 

1024  ; Bow-pen,  No.  1041  ; Drawing-Pens,  Nos. 

1055  and  1057  ; Box  of  Leads 17.00  .20 


1104. 


1104.  Morocco  Case,  containing  : 

Hairspring  Dividers,  No.  1008  ; Compasses,  No. 

1024 ; Bow-spacer,  No.  1039 ; Bow-pen,  No. 

1041  ; Bow-pencil,  No.  1042 ; Drawing-Pens, 

Nos.  1055  and  1057  ; Box  of  Leads 22.00  .25 

1 105.  Polished  Mahogany  Box,  with  lock  and  tray,  containing  : 

Hairspring  Dividers,  No.  1008  ; Compasses,  Nos. 

1019  and  1024;  Drawing-Pens,  Nos.  1055  and 

1056  ; Box  of  Leads 21.00  .40 

1106.  Polished  Mahogany  Box,  with  lock  and  tray,  containing  : 

Plain  Dividers,  No.  1003  ; Hairspring  Dividers, 

No.  1008 ; Compasses,  Nos.  1018  and  1022  ; 

Bow-spacer,  No.  1033  ; Bow-pen,  No.  1034 ; 

Bow-pencil,  No.  1035;  Drawing-Pens,  Nos. 

1055  and  1056  ; Box  of  Leads 27.00  .45 


W.  & L.  E.  GURLEY,  TROY,  N.  K 


297 


SUPERIOR  SWISS  DRAWING- INSTRUMENTS, 
WITH  PERFECT  PIVOT-JOINTED  HEADS. 


1112. 

1116.  1119.  1122. 

1130. 

No. 

Price. 

Post. 

1110. 

Plain  Dividers,  3J-inch 

$2.00 

$0.10 

1111. 

Plain  Dividers,  4J-inch 

2.35 

.12 

1112. 

Plain  Dividers,  5-inch 

2.50 

.12 

1114. 

Hairspring  Dividers,  3J-inch 

2.50 

.10 

208 


W.  & L.  E.  GURLEY,  TROY , N.  K 


No. 

1115. 

1116. 

1119. 

1120. 
1122. 
1124. 
1126. 
1128. 

1130. 

1132. 


1135. 

1136. 

1137. 

1138. 


Price.  Post. 


Hairspring  Dividers,  4}-inch $3.00  $0.12 

Hairspring  Dividers,  5-inch 3.25  .12 

Compasses,  3J-inch,  with  fixed  needle  and  pen 

points 3.35  .10 

Compasses,  3J-inch,  with  fixed  needle  and  pencil 

points 3.35  .10 

Compasses,  3J-inch,  with  fixed  needle  point,  and 

pen  and  pencil  points 5.00  .12 

Compasses,  3J-inch,  with  fixed  needle  point  with 

hairspring,  and  pen  and  pencil  points 6.00  .12 

Compasses,  4J-inch,  with  fixed  needle  point,  pen 

and  pencil  points  and  lengthening  bar 6.25  .15 

Compasses,  4J-inch,  with  fixed  needle  point  with 
hairspring,  pen  and  pencil  points  and  lengthening 

bar 7.25  .15 

Compasses,  5J-inch,  with  fixed  needle  point,  pen 

and  pencil  points  and  lengthening  bar 6.50  .15 

Compasses,  5J-inch,  with  fixed  needle  point  with 
hairspring,  pen  and  pencil  points  and  lengthening 
bar 7.50  .15 


1135. 


1137.  1138. 


Steelspring  Bow-spacer,  3-inch,  with  metal  handle..  1.50 
Steelspring  Bow-spacer,  3-inch,  with  needle  points 

and  metal  handle 2.25 

Steelspring  Bow-pen,  3-inch,  with  metal  handle 2.25 

Steelspring  Bow-pencil,  3-inch,  with  metal  handle..  2.25 


.10 

.10 

.10 

.10 


290 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 


(For  prices,  see  pages  298  and  300.) 


1148.  1147 


300 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 


No.  Price.  Post. 

1140.  Steelspring  Bow-spacer,  3J-inch,  with  wheel  adjust- 
ment  $2.00  $0.10 

1142.  Steelspring  Bow-pen,  3J-inch,  with  wheel  adjust- 

ment  ‘. 2.75  .10 

1143.  Steelspring  Bow-pencil,  3J-inch,  with  wheel  adjust- 

ment  2.75  .10 

1147.  Drawing-pen,  with  spring  blade,  ebony  handle, 

4finch 1.10  .10 

1148.  Drawing-pen,  with  spring  blade,  ebony  handle, 

5-inch 1.20  .10 

1149.  Drawing-pen,  with  spring  blade,  ebony  handle, 

5J-inch 1.35  .10 


CASES  OF  SWISS  DRAWING-INSTRUMENTS 
WITH  PIVOT-JOINTED  HEADS. 

1160.  Morocco  Case,  containing  : 

Plain  Dividers,  No.  1110  ; Compasses,  No.  1122  ; 

Drawing-pen,  No.  1147  ; Box  of  Leads $9.00  $0.15 

1161.  Morocco  Case,  containing: 

Hairspring  Dividers,  No.  1115  ; Compasses,  No. 

1126;  Drawing-pen,  No.  1148;  Box  of  Leads...  12.00  .15 


1162. 

1162.  Morocco  Case,  containing  : 

Hairspring  Dividers,  No.  1114  ; Compasses,  Nos. 
1119  and  1120;  Drawing-pen,  No.  1147;  Box 


of  Leads j 12.00  .15 

1163.  Morocco  Case,  containing  : 

Hairspring  Dividers,  No.  1115  ; Compasses,  No. 

1126  ; Bow-pen,  No.  1137  ; Drawing-pens,  Nos. 

1147  and  1148;  Box  of  Leads 16.00 


.20 


W.  Z.  E.  GURLEY,  TROY,  N.  Y 


301 


No.  Price.  Post. 

1164.  Morocco  Case,  containing  : 

Hairspring  Dividers,  No.  1116  ; Compasses,  Nos. 

1124  and  1130;  Drawing-pens,  Nos.  1147  and 

1148  ; Box  of  Leads $20.00  $0.20 

1165.  Morocco  Case,  containing  : 

Hairspring  Dividers,  No.  1116  ; Compasses,  No. 

1130;  Bow-spacer,  3 J-inch  ; Bow-pen,  3 J-inch  ; 

Bow-pencil,  3J-inch  ; Drawing-pens,  Nos.  1147 

and  1148;  Box  of  Leads 21.50  .25 


1165-1166. 


1166.  Morocco  Case,  containing: 

Hairspring  Dividers,  No.  1115;  Compasses,  No. 

1126;  Bow-spacer,  No.  1135;  Bow-pen,  No. 

1137;  Bow-pencil,  No.  1138;  Drawing-pens, 

Nos.  1147  and  1148  ; Box  of  Leads 20.00  .20 

1167.  Morocco  Case,  containing: 

Hairspring  Dividers,  No.  1116  ; Compasses,  Nos. 

1124  and  1130;  Bow-pen,  No.  1137  ; Drawing- 

pens,  Nos.  1147,  1148  and  1149  ; Box  of  Leads..  24.00  .25 

1168.  Folding  Pocket  Case  with  flexible  flaps  (see  page 

307),  and  containing  same  instruments  as  in  set 

No.  1166 21.25  .20 


302 


W.  & Z.  E.  GURLEY,  TROY,  N.  Y. 


ALTENEDER’S  PATENT  JOINT  GERMAN  SIL- 
VER AND  STEEL  DRAWING-INSTRUMENTS. 

(warranted  genuine.) 


The  excellence  of  these  instruments  consists  in  the  joints  of  the 
dividers  being  so  constructed  as  to  prevent  any  irregular  motion  when 
the  legs  are  opened  or  closed,  also  for  the  general  care  with  which  the 
instruments  are  finished.  All  the  pens  are  well  made  and  pointed. 


Alteneder’s 
Patent  Joint. 


Knuckle-  Clamp - 

Joints.  Holders. 


Clamp - 
Sockets. 


No.  Price.  Post. 

1170.  Plain  Dividers,  3J-inch $ 2.25  $0.10 

1171.  Plain  Dividers,  4J-inch 2.50  .12 

1172.  Plain  Dividers,  5-inch 2.50  .12 

1174.  Hairspring  Dividers,  3J-inch 3.50  .10 

1175.  Hairspring  Dividers,  4^-inch 3.75  .12 

1176.  Hairspring  Dividers,  5-inch t 4.00  .12 

1180.  Compasses,  3J-inch,  with  fixed  needle  and  pen 

points f 4.00  .10 

1181.  Compasses,  3^-inch,  with  fixed  needle  and  pencil 

points 4.00v  .10 

1182.  Compasses,  4J-inch,  with  fixed  needle  and  pen 

points  4.50  .12 

1183.  Compasses,  4J-inch,  with  fixed  needle  and  pencil 

points  4.50  .12 


(See  cuts  on  pages  303  and  304.) 


w.  & L.  E.  GURLEY,  TROY,  N.  Y 


303 


1171.  1175.  1182.  1183.  • 1187. 

(For  prices,  see  pages  302  and  305.) 


304 


W.  &>  L.  E.  GURLEY,  TROY,  N.  Y. 


1190. 


1195.  1196. 


1197. 

(For  prices,  see  page  305.) 


1198. 


W.  & L.  E.  GURLEY,  TROY,  N.  Y.  305 

No.  Price.  Post. 

1184.  Compasses,  5|-inch,  with  fixed  needle  and  pen 

points |5.00  $0.12 

1185.  Compasses,  5J-inch,  with  fixed  needle  and  pencil 

points 5.00  .12 

1186.  Compasses,  3J-inch,  with  fixed  needle  point,  and 

pen  and  pencil  points * 6.00  .12 

1187.  Compasses,  3J-inch,  with  fixed  needle  point  with 

hairspring,  and  pen  and  pencil  points 7.50  .12 

(See  cut  of  No.  1187  on  page  303.) 

1188.  Compasses,  4J-inch,  with  fixed  needle  point,  and  pen 

and  pencil  points  and  lengthening  bar 7.25  .14 

1189.  Compasses,  4J-inch,  with  fixed  needle  point  with 

hairspring,  and  pen  and  pencil  points  and  length- 
ening bar 8.75  .14 

1190.  Compasses,  5J-inch,  with  fixed  needle  point,  pen 

and  pencil  points  and  lengthening  bar 7.50  .15 

1191.  Compasses,  5J-inch,  with  fixed  needle  point  with 

hairspring,  pen  and  pencil  points  and  lengthening 

bar 9.00  .15 

1195.  Steelspring  Bow-spacer,  metal  handle,  3J-inch 1.75  .10 

1196.  Steelspring  Bow-spacer,  needle-points,  metal  handle, 

3J-inch 2.50  .10 

1197.  Steelspring  Bow-pen,  needle  point,  metal  handle, 

3J-inch 2.50  .10 

1198.  Steelspring  Bow-pencil,  needle  point,  metal  handle, 

3J-inch 2.50  .10 

(See  cuts  of  Nos.  1190-1198  on  page  304.) 


1206. 


1206.  Drawing-pen,  with  spring  blade,  ebony  handle, 

4i-inch  1.40  .10 

1207.  Drawing-pen,  with  spring  blade,  ebony  handle, 

5-inch 1.65  .10 

1208.  Drawing-pen,  with  spring  blade,  ebony  handle, 

5i-inch 1.90  .10 

1209.  Drawing-pen,  with  patent  spring  hinge,  ebony 

handle,  5-inch 2.90  .10 

1210.  Railroad-pen,  ebony  handle,  5-inch 3.50  .10 

1211.  Swivel  Curve-pen,  spring  blade,  hollow  metal 

handle 2.00  .10 

1212.  Pricker,  with  removable  needle  point,  ebony  handle,  1.00  .10 

1214.  Nickel-plated  case,  for  leads 15  .02 


306 


IV.  &"  L.  E.  GURLEY,  TROY,  N.  Y. 


ALTENEDER’S  PATENT  JOINT  DRAWING  - IN- 
STRUMENTS IN  MOROCCO  CASES. 


No.  Price.  Post. 

1220.  Morocco  Case  containing  : 

Compasses,  Nos.  1180  and  1181  ; Drawing-Pen, 

No.  1206;  Box  of  Leads $10.75  $0.15 

1222.  Morocco  Case,  containing  : 

Hairspring  Dividers,  No.  1175  ; Compasses,  No. 

1188;  Drawing-Pen,  No.  1207;  Box  of  Leads..  14.25  .18 

1224.  Morocco  Case,  containing  : 

Hairspring  Dividers,  No.  1175  ; Compasses,  No. 

1189;  Bow-pen,  No.  1197;  Drawing-Pen,  No. 

1207  ; Box  of  Leads 18.50  .20 


1225. 


1225.  Morocco  Case,  containing  : 

Hairspring  Dividers,  No.  1176  ; Compasses,  No. 

1190  ; Bow-spacer,  No.  1195  ; # Bow-pen,  No. 

1197;  Bow-pencil,  No.  1198;  Drawing-Pens, 

Nos.  1206  and  1207  ; Box  of  Leads 23.50  .20 

1227.  Morocco  Case,  containing  : 

Hairspring  Dividers,  No.  1176  ; Compasses,  No. 

1191;  Bow-spacer,  No.  1195;  Bow-pen,  No. 

1197;  Bow-pencil,  No.  1198;  Drawing-Pens, 

Nos.  1206  and  1207  ; Box  of  Leads 25.00  .25 

1228.  Morocco  Case,  containing  : 

Hairspring  Dividers,  No.  1176  ; Compasses,  Nos. 

1186  and  1190;  Bow-spacer,  No.  1195;  Bow- 

pen,  No.  1197  ; Bow-pencil,  No.  1198  ; Drawing- 

Pens,  Nos.  1206  and  1207  ; Box  of  Leads 30.00  .30 


IV.  er=  L.  E.  GURLEY,  TROY,  N.  K 307 


1230. 

No.  Price.  Post. 

1230.  Folding  Pocket  Case,  with  flexible  flaps,  and  con- 
taining same  instruments  as  in  set  No.  1225 $24.75  $0.20 

1232.  Empty  Folding  Pocket  Case,  with 
flexible  flaps,  and  fitted  to  re- 
ceive from  five  to  twelve  pieces 

of  drawing-instruments ; price,  price.  post. 

according  to  size  of  case $3.00  to  $4.00  $0.12  to  $0.20 

Note. — Folding  Pocket  Cases  furnished,  instead  of  the  usual 
Morocco  Cases,  with  sets  Nos.  1220-1228,  at  an  extra  cost  of  $1.25. 


308 


W.  & L.  E.  GURLEY,  TROY,  N.  Y. 


BEST  GERMAN  DRAWING  - INSTRUMENTS. 

OF  FINE  GERMAN  SILVER  AND  STEEL. 


(For  prices  of  empty  cases  for  Drawing-Instruments,  see  page  294.) 


1247. 


(For  prices,  see  page  309.  Nos.  1237,  1241  and  1247  are  now  made  with  handles.) 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y.  309 

No.  Price.  Post. 

1235.  Plain  Dividers,  3J-inch,  with  handle $0.70  $0.02 

1237.  Plain  Dividers,  5-inch,  with  handle 80  .03 

1238.  Plain  Dividers,  6-inch,  with  handle 1.00  .04 

1240.  Hairspring  Dividers,  3J-inch,  with  handle 1.20  .10 

1241.  Hairspring  Dividers,  5-inch,  with  handle 1.50  .11 

1242.  Hairspring  Dividers,  6-inch,  with  handle 1.75  .12 

1245.  Compasses,  3J-inch,  with  pen,  pencil  and  needle 

points 2.50  .12 


1247.  Compasses,  5J-inch,  with  pen,  pencil  and  needle 

points  and  lengthening^ bar 3.00  .15 


1253. 


1257. 


1250 


1251 


310 


IV.  &*  L.  E.  GURLEY,  TROY,  N.  Y. 


No.  Price.  Post. 

1250.  Pocket  Dividers,  5-inch  with  sheath $1.50  $0.12 

1251.  Three-legged  Dividers,  5-inch,  for  taking  off  three 

points 2.75  .13 

1253.  Proportional  Dividers,  6J-inch,  divided  for  lines 2.50  .15 

1254.  Proportional  Dividers,  7-inch,  for  lines  and  circles.  3.25  .15 

1255.  Proportional  Dividers,  7-inch,  with  rack  movement 

and  divided  for  lines  and  circles 5.20  .15 

1257.  Pocket-Compasses,  with  folding  points 5.00  .12 


1258. 

1259.  1260 

BearmCompass  Furniture,  with  pen,  pencil  and 
needle  points,  with  tangent  adjustment,  in  case ... 

5.00 

.16 

1259. 

Beam-Compass  Furniture,  with  pen,  pencil  and 

needle  points,  in  morocco  case 

Universal  Map-Measurer.  The  index-hand  registers 
inches  to  miles,  or  centimeters  to  kilometers 

5.00 

.16 

1260. 

3.00 

.12 

1267. 

Steelspring  Bow-spacer,  ivory  handle,  3J-inch 

1.00 

.10 

1268. 

Steelspring  Bow-pen,  ivory  handle,  3J-inch 

1.25 

.10 

1269. 

Steelspring  Bow-pencil,  ivory  handle,  3J-inch 

1.25 

.10 

W.  & L.  E.  GURLEY,  TROY,  N.  Y 


311 


! 

1269. 


No. 

1270. 

1275. 

1276. 

1277. 

1278. 


1270. 


Price. 


Set  of  three  Steel  Bows,  Nos.  1267,  1268  and  1269 

in  morocco  case $4.20 

Bow-spacer,  Vith  wheel  adjustment,  metal  handle, 

3 \ -inch 1.50 

Bow-pen,  with  wheel  adjustment,  metal  handle  3J- 

inch 1.75 

Bow-pencil,  with  wheel  adjustment,  metal  handle, 

3J-inch 1.75 

Set  of  three  Steel  Bows,  Nos.  1275,  1276  and  1277 
in  morocco  case 5.75 


Post. 

$0.15 

.10 

.10 

.10 

.15 


312 


tv  A-  L.  E.  GURLEY , TROY,  N.  Y. 


1280.  1282. 

(For  prices,  see  pages  311  and  313.) 


1279. 


1283. 


W.  <Sr*  L.  E.  GURLEY,  TROY , N.  Y. 


313 


No.  Price.  Post. 

1279.  Spring  Bow-pen,  with  adjusting-screw $1.40  $0.10 

1280.  Spring  Bow-pen,  with  pencil  leg  and  adjusting-screw  2.00  .10 

1282.  Spring  Bow-pen,  with  adjustable  needle  point  for 

small  circles 2.50  .10 

1283.  Spring  Bow-pen,  with  pencil  leg,  and  adjustable 

needle  point  for  small  circles 3.50  .10 

1284.  Spring  Bow-pen,  with  spring  needle  point  for  small 

circles 2.75  .10 

1290.  Drawing-Pen,  without  joint,  ivory  handle,  4^-inch..  .35  .02 

1292.  Drawing-Pen,  without  joint,  ivory  handle,  5J-inch..  .40  .03 

1294.  Drawing-Pen,  with  fine  joint,  ivory  handle,  4J-inch  .50  .02 

1295.  Drawing-Pen,  with  fine  joint,  ivory  handle,  5-inch..  .55  .03 

1296.  Drawing-Pen,  with  fine  joint,  ivory  handle,  5J-inch  .60  .03 


1294.  1295.  1297.  1298.  1300.  1301. 


314  IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 

No.  Price.  Post. 

1297.  Drawing-Pen,  with  fine  joint  and  pin,  ivory  handle, 

4J-inch $0.65  $0.02 

1298.  Drawing-Pen,  with  fine  joint  and  pin,  ivory  handle, 

5-inch 70  .03 

1299.  Drawing-Pen,  with  fine  joint  and  pin,  ivory  handle, 

5J — 6-inch 75  03 

1300.  Drawing-Pen,  without  set-screw,  hollow  metal 

handle,  5J-inch 1.45  .10 

1301.  Drawing-Pen,  Swedish  pattern,  ebony  handle, 

5- inch 75  .03 

1302.  Drawing-Pen,  Swedish  pattern,  ebony  handle, 

6- inch 85  .03 

1303.  Drawing-Pen,  with  German  silver  blades,  for  red 

ink,  5-inch 65  .03 

1304.  Curve-Pen,  ivory  handle,  4J-inch 1.25  .10 

1305.  Curve-Pen,  swivel  blade,  hollow  metal  handle, 

5-inch 1.50  *.10 

1306.  Drawing-Pen,  for  heavy  border  lines,  ivory  handle, 

5i-inch 2.00  .10 

1307.  Railroad  Pen,  with  joints,  ivory  handle,  5J-inch 2.25  .10 

1308.  Railroad  Pen,  with  ivory  handle,  5J-inch,  will  draw 

with  one  stroke  one  broad  or  two  parallel  lines  of 

the  same  or  different  widths 3.00  .10 

1310.  Pricker,  ivory  handle 1.20  .10 

1312.  Tracer,  ivory  handle 90  .02 

1314.  Dotting-Pen,  one  wheel,  ivory  handle,  5-inch 1.00  .03 

1316.  Dotting-Pen,  with  six  wheels,  extra  fine,  in  Morocco 

case..... 3.75  .12 

The  outer  wheel  is  rolled  on  the  edge  of  a ruler  and  turns  the  ratchet 
wheel,  which  causes  the  pen  to  move  up  and  down.  The  flat  point  near 
the  pen  must  slide  on  the  paper. 

(For  cuts  of  Nos.  1304-1316,  see  page  315.) 


w.  & L.  E.  GURLEY,  TROY,  N.  Y 


1304.  1305.  1307.  1308. 


(For  prices,  see  page  314.) 


1312. 


315 


1314. 


316  W.  & L.  E.  GURLEY, \ TROY,  N.  Y. 

CASES  OF  FINE  GERMAN  SILVER  INSTRUMENTS. 


FOR  ENGINEERS,  ARCHITECTS,  AND  MACHINISTS. 


No. 

Price. 

Post. 

1330. 

Morocco  Case,  containing : 

Compasses,  No.  1245  ; Drawing-pen,  No.  1294  ; 
Box  of  Leads 

|3.25 

$0.12 

1331. 

Morocco  Case,  containing : 

Plain  Dividers,  No.  1235  ; Compasses,  No.  1245  ; 
Drawing-pen,  No.  1294  ; Box  of  Leads 

4.00 

.13 

1333. 

Morocco  Case,  containing  : 

Plain  Dividers,  No.  1237 ; Compasses,  5J-inch, 
with  fixed  needle  point,  pen  and  pencil  points ; 
Drawing-pen,  No.  1295  ; Box  of  Leads 

3.50 

.15 

1334. 

Morocco  Case,  containing : 

Plain-Dividers,  No.  1237 ; Compasses,  5J-inch, 
with  fixed  needle  point,  pen  and  pencil  points ; 
Bow-pen,  No.  1268 ; Drawing-pen,  No.  1295 ; 
Box  of  Leads 

4.75 

.18 

1335. 

Morocco  Case,  containing : 

Plain  Dividers,  No.  1237  ; Compasses,  No.  1247  ; 
Drawing-pen,  No.  1299  ; Box  of  Leads 

5.00 

.18 

1330.  1337. 


1337.  Morocco  Case,  containing : 

Spring  Bow-compasses,  3J-inch,  with  long  detach- 
able handle,  two  pen  points,  pencil  and  needle 
points;  Dra.wing-pen,  No.  1297;  Box  of  Leads  5.00  .18 


W.  &>  L.  E.  GURLEY, \ TROY,  N.  Y. 


317 


1339. 


No.  Price.  Post. 

1339.  Morocco  Case,  containing  : 

Plain  Dividers,  No.  1237  ; Compasses,  No.  1247  ; 

Bow-pen,  No.  1268 ; Drawing-pen,  No.  1299 ; 

Box  of  Leads * $6.50  $0.18 


1340. 

1340.  Morocco  Case,  containing  : 

Plain  Dividers,  No.  1237  ; Compasses,  Nos.  1245 
and  1247  ; Dravring-pens,  Nos.  1297  and  1299 ; 

Box  of  Leads 8.75  .20 

1341.  Morocco  Case,  containing: 

Plain  Dividers,  No.  1237 ; Compasses,  Nos.  1245 
and  1247  ; Bow-pen,  No.  1268  ; Drawing-pens, 

Nos.  1297  and  1299  ; Box  of  Leads 10.00  .20 

1342.  Morocco  Case,  containing: 

Plain  Dividers,  No.  1241  ; Compasses,  No.  1247 ; 

Bow-spacer,  No.  1267 ; Bow-pen,  No.  1268 ; 

Bow-pencil,  No.  1269 ; Drawing-pens,  Nos. 

1297  and  1299  ; Box  of  Leads 10.00 


.20 


W.  & L.  E.  GURLEY,  TROY,  N.  Y 


Pkice.  Post. 

Polished  Mahogany  Box,  with  lock  and  tray,  con- 
taining : 

Plain  Dividers,  No.  1237  ; Hairspring  Dividers, 

No.  1241  ; Compasses,  Nos.  1245  and  1247 ; 

Bow-pen,  No.  1279  ; Drawing-Pens,  Nos.  1297 

and  1299  ; Box  of  Leads $14.50  $0.45 

Polished  Mahogany  Box,  with  lock  and  tray,  con- 
taining : 

Hairspring  Dividers,  No.  1241  ; Compasses,  Nos. 

1245  and  1247  ; Proportional  Dividers,  No.  1253  ; 

Bow-pen,  No.  1268;  Drawing-Pens,  Nos.  1297 

and  1299  ; Box  of  Leads 16.00  .50 

Polished  Mahogany  Box,  with  lock  and  tray,  con- 
taining : 

Hairspring  Dividers,  No.  1241  ; Compasses,  No. 

1247  ; Proportional  Dividers,  No.  1253 ; Bow- 
spacer,  No.  1267 ; Bow-pen,  No.  1268 ; Bow- 
pencil,  No.  1269 ; Railroad  Pen,  No.  1307 ; 

Curve -Pen,  No.  1304;  Drawing-Pens,  Nos. 

1297,  1299  and  1301  ; Box  of  Leads 20.00  .55 

Polished  Mahogany  Box,  with  lock  and  tray,  con- 
taining : 

Plain  Dividers,  No.  1237  ; Hairspring  Dividers, 

No.  1241  ; Compasses,  Nos.  1245  and  1247 ; 

• Proportional  Dividers,  No.  1255  ; Bow-spacer, 

No.  1275  ; Bow-pen,  No.  1276  ; Bow-pencil, 

No.  1277  ; Railroad  Pen,  No.  1308;  Curve-Pen, 

No.  1305  ; Drawing-Pens,  Nos.  1294,  1298  and 

1301;  Beam-Compass,  No.  1259  ; Box  of  Leads..  35.00  .75 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 


319 


SETS  OF  PIVOT- JOINT  INSTRUMENTS  OF  BEST 
GERMAN  MAKE. 

FINE  GERMAN  SILVER  AND  STEEL. 


No. 

Price. 

Post. 

1355. 

Morocco  Case,  containing : 

Plain  Dividers,  5-inch  ; Compasses,  5^-inch,  with 
fixed  needle  point,  pen  and  pencil  points  and 
lengthening  bar  ; Drawing-Pen  ; Box  of  Leads... 

|9.00 

$0.15 

1356. 

Morocco  Case,  containing  : 

Plain  Dividers,  3J-inch  ; Compasses,  3J-inch, 
with  fixed  needle  and  pen  points  ; Compasses, 
3J-inch,  with  fixed  needle  and  pencil  points ; 
Drawing-Pen  ; Box  of  Leads 

10.00 

.15 

1358.  Morocco  Case,  containing  : 

Hairspring  Dividers,  5-inch  ; Compasses,  5J-inch, 
with  fixed  needle  point,  pen  and  pencil  points 
and  lengthening  bar  ; Bow-spacer  ; Bow-pen  ; 

Bow-pencil;  Two  Drawing-Pens  ; Box  of  Leads  12.60  .20 

1360.  Morocco  Case,  containing  : 

Plain  Dividers,  5-inch  ; Compasses,  5}-inch,  with 
fixed  needle  point,  pen  and  pencil  points  and 
lengthening  bar ; Compasses,  3J-inch,  with  fixed 
needle  and  pen  points  ; Compasses,  3J-inch,  with 
fixed  needle  and  pencil  points ; Two  Drawing- 
Pens ; Box  of  Leads 15.00  ,20 


320  W.  &■  L.  E.  GURLEY \ TROY,  AT.  Y. 


1360. 

(For  price,  see  page  319.) 


SETS  OF  GERMAN  SILVER  DRAWING -INSTRU- 
MENTS FOR  SCHOOL  USE. 


1365. 


No.  Price.  Post. 

1365.  Leather  Case,  containing  : 

Plain  Dividers,  5-inch  ; Compasses,  5J-inch,  with 
fixed  needle  point,  pen  and  pencil  points  and 
lengthening  bar;  Drawing-Pen;  Box  of  Leads...  $3.00  $0.13 
1367.  Leather  Case,  containing  : 

Plain  Dividers,  5-inch  ; Compasses,  5J-inch,  with 
fixed  needle  point,  pen  and  pencil  points  and 
lengthening  bar  ; Bow-pen  ; Drawing-Pen  ; Box 

of  Leads 4.00  .15 

1369.  Leather  Case,  containing  : 

Plain  Dividers,  5-inch  ; Compasses,  5J-inch,  with 
steel  points,  pen,  pencil  and  needle  points  and 
lengthening  bar  ; Bow-spacer  ; Bow-pen  ; Bow- 
pencil ; Drawing-Pen  -}  Box  of  Leads.  6,00  *18 


W.  dr*  L.  E.  GURLEY,  TROY,  N.  Y. 


321 


1369. 

(For  price,  see  page  320.) 

No.  Price.  Post. 

1371.  Leather  Case  containing  : 

Plain  Dividers,  5-inch ; Compasses,  3J-inch, 
with  steel  points,  pen,  pencil  and  needle  points ; 

Compasses,  5J-inch,  with  steel  points,  pen,  pencil 
and  needle  points  and  lengthening  bar ; Bow- 
spacer  ; Bow-pen  ; Bow-pencil ; Two  Drawing- 
Pens  ; Box  of  Leads 19.00  $0.20 


322  ' W.  <5r»  L.  E.  GURLEY,  TROY,  N.  Y 

BRASS  DRAWING- INSTRUMENTS. 


FOR  SCHOOL  USE. 


1386.  1389.  1393.  1397.  1400. 

No.  Price.  Post. 

1375.  Plain  Dividers,  rivet  joint,  4-inch $0.15  $0.02 

1376.  Plain  Dividers,  rivet  joint,  5-inch 20  .03 

1378.  Plain  Dividers,  screw  joint,  4-inch 20  .02 

1379.  Plain  Dividers,  screw  joint,  5-inch 25  .03 

1382.  Compasses,  3-inch,  with  pen  point. 35  .03 


W.  &>  L.  E.  GURLEY, , TROY,  N.  Y.  323 

No.  Price.  Post. 

1383.  Compasses,  3-inch,  with  pencil  point $0.35  $0.03 

1384.  Compasses,  3-inch,  with  pen,  pencil  and  needle 

points  40  .04 

1385.  Compasses,  4J-inch,  with  pien  and  pencil  points  and 

lengthening  bar ,50  .05 

1386.  Compasses,  4J-inch,  with  fixed  needle  point,  pen 

and  pencil  points,  and  lengthening  bar * ,60  .05 

1387.  Compasses,  6-inch,  with  pen  and  pencil  points,  and 

lengthening  bar 65  .08 

1388.  Compasses,  6-inch,  with  fixed  needle  point,  pen  and 

pencil  points,  and  lengthening  bar 75  .08 

1389.  Spring  bow-pen,  with  needle  point,  3-inch 60  .02 

1391.  Roulette,  with  three  wheels,  for  dotting  lines 75  .03 

1393.  Proportional  Dividers,  6J-inch,  divided  for  lines 1.50  .13 

1395.  Drawing-Pen,  wood  handle 15  .02 

1396.  Drawing-Pen,  bone  handle .20  .02 

1397.  Railroad  Drawing-Pen 1.50  .10 

1400.  Wood  Dividers,  with  crayon  holder,  12- inch 1.00  .15 

1401.  Wood  Dividers,  with  crayon  holder,  15-inch 1.25  .18 

1402.  Wood  Dividers,  with  crayon  holder,  18-inch 1.50  .20 


CASES  OF  BRASS  DRAWING-INSTRUMENTS. 

FOR  SCHOOL  USE. 

1405.  Rosewood  Box,  containing  : 

Plain  Dividers,  4J-inch  ; Compasses,  4-inch,  with 
pen  and  pencil  points  ; Compasses,  6 -inch,  with 
pen  and  pencil  points  and  lengthening  bar ; 

Drawing  - Pen  ; Brass  and  Horn  Protractors  ; 

Wood  Rule $2.00  $0.23 


1406.  Rosewood  Box,  with  lock  and  tray,  containing  : 

Plain  Dividers,  4J-inch  ; Compasses,  4-inch,  with 
fixed  needle  point,  pen  and  pencil  points  ; Com- 
passes, 6-inch,  with  fixed  needle  point,  pen  and 
pencil  points  and  lengthening  bar  ; Drawing-Pen  ; 

Brass  and  Horn  Protractors  ; Wood  Rule 3.00  .28 

1407.  Rosewood  Box,  etc. , same  as  No.  1406,  and  with 

addition  of  Spring  Bow-pen 3.75  .28 

1408.  Rosewood  Box,  etc.,  same  as  No.  1406,  and  with 

addition  of  Spring  Bow-pen,  Proportional  Divid- 
ers, Triangle  and  Irregular  Curve,  and  omitting 
Brass  Protractor 5.50  .35 


324 


W.  & L.  E.  GURLEY,  TROY,  N.  Y. 


NICKEL  - PLATED  DRAWING  - INSTRUMENTS. 


1413.  1416.  1418.  1420. 


1425  AND  1427. 


(For  prices  of  Nos.  1413-1427,  see  page  325.) 


325 


. IV.  & L.  E.  GURLEY,  TROY,  N.  K 

NICKEL  - PLATED  BRASS  DRAWING  - INSTRU- 
MENTS. 


FOR  SCHOOL  USE.  (See page  32U.) 

No.  Price.  Post. 

1410.  Plain  Dividers,  rivet  joint,  4J-inch . $0.20  $0.02 

1411.  Plain  Dividers,  rivet  joint,  5|-inch 25  .03 

1413..  Plain  Dividers,  screw  joint,  4J-inch 25-  .02 

1414.  Plain  Dividers,  screw  joint,  5Jrinch 30  .03 

1416.  Compasses,  4J-inch,  with  pencil  point . .35  .03 

1418.  Compasses,  4 J -inch,  with  pen  and  pencil  points ^0  .04 

1420.  Compasses,  4J-inch,  with  pen  and  pencil  points  and 

lengthening  bar .65  .05 

1425.  Drawing-Pen,  black  wood  handle,  5-inch .^0  .03 

1427.  Drawing-Pen,  bone  handle,  5-inch .$0  .03 

. ' ■{ 


SETS  OF  NICKEL -PLATED  DRAWING- INSTRU- 
MENTS IN  LEATHERETTE  CASES. 

FOR  SCHOOL  USE. 


1430.  Case,  containing  : 

Compasses,  4J-inch,  with  pen  and  pencil  points ; 

Box  of  Leads  ; Color  "Saucer $0.65  $0.08 

1431.  Case,  containing  : 

Compasses,  4J-inch,  with  pen  and  pencil  points  ; 

Drawing  - Pen  ; Box  of  Leads  ; Color  - Saucer  ; 

Protractor,  Ruler  and  Triangle 85  .10 


1433. 


326 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 


No. 

1433. 


Prick.  Post. 

Case,  containing  : 

Plain  Dividers,  4-inch ; Compasses,  4J-inch, 
with  pen  and  pencil  points  ; Drawing-Pen  ; Box 
of  Leads;  Color  - Saucers  ; Protractor,  Ruler  and 
Triangle $1.20  $0.15 


1435. 


1435.  Case,  containing  : 

Plain  Dividers,  4-inch  ; Compasses,  3 -inch,  with 
pen,  pencil  and  needle  points ; Compasses, 

4J-inch,  with  pen  and  pencil  points  and  lengthen- 
ing bar;  Drawing-Pen;  Box  of  Leads;  Color- 
Saucers;  Protractor,  Ruler  and  Triangle 1.80  .18 

1436.  Case,  containing  : 

Plain  Dividers,  4-inch  ; Compasses,  4J-inch,  with 
pen  and  pencil  points  and  lengthening  bar ; 

Spring  Bow-pen  ; Drawing-Pen  ; Box  of  Leads  ; 

Color- Saucers  ; Protractor,  Ruler  and  Triangle...  2.00  .20 


W.  & L.  E.  GURLEY,  TROY,  N.  Y. 


327 


PROTRACTORS. 


EXTRA  FINE  SWISS  GERMAN  SILVER  PRO- 
TRACTORS. 


on  outer  edge,  divided  to  1 degree $1.50  $0.12 

1441.  Protractor,  half  circle,  5-inch,  divided  to  J degrees..  2.25  .13 

1442.  Protractor,  half  circle,  6-inch,  divided  to  J degrees..  2.75  .15 

1443.  Protractor,  half  circle,  6-inch,  divided  to  J degrees..  3.50  .15 


1445.  Protractor,  half  circle,  5-inch,  beveled  edge,  center 

on  inner  edge,  divided  to  J degrees 2.75  .14 

1446.  Protractor,  half  circle,  6-inch,  divided  to  \ degrees..  3.50  .16 

1447.  Protractor,  half  circle,  6-inch,  divided  to  J degrees..  4.25  .16 

1450.  Protractor,  whole  circle,  5-inch,  divided  to  } degrees  5.00  .20 


328 


W.  &>  L.  E.  GURLEY,  TROY,  N.  V 


EXTRA  FINE  SWISS  GERMAN  SILVER 
PROTRACTORS,  WITH  ARM  AND 


No. 

WITHOUT  VERNIER. 

Price. 

Post. 

1454. 

Protractor,  half  circle,  6-inch, 
with  horn  center  and  6 -inch 
movable  arm,  divided  to  J 
degrees 

$7.50 

$0.20 

1455. 

Protractor,  half  circle,  7-inch, 
with  horn  center  and  6 -inch 
movable  arm,  divided  to  J 
degrees 

9.00 

.25 

Length  of  arms  extending  over 
the  outer  edge  of 
Protractors. 


For  Nos.  1460  and  1465,  5J-inch. 
For  Nos.  1461,  1466,  1470,  6-inch. 
For  Nos.  1462,  1467,  1473,  6J-inch. 


°i'  <** 

1461. 


EXTRA  FINE  SWISS  GERMAN  SILVER  PRO- 
TRACTORS WITH  ARM  AND  VERNIER. 

No.  Price.  Post. 

1460.  Protractor,  half  circle,  5J-inch,  with  horn  center 

and  movable  arm,  divided  to  J degrees,  vernier 

reading  to  3 minutes $10.00  $0.20 

1461.  Protractor,  half  circle,  8-inch,  divided  to  J degrees, 

vernier  to  1 minute 14.00  .25 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y 


329 


No.  Prick.  Post. 

1462.  Protractor,  half  circle,  10-inch,  divided  to  J .degrees, 

vernier  to  1 minute $17.00  $0.35 

1465.  Protractor,  whole  circle,  5J-inch,  with  horn  center 

and  movable  arm,  divided  to  J degrees,  vernier 

reading  to  3 minutes 14.00  .30 

1466.  Protractor,  whole  circle,  8-inch,  divided  to  \ degrees, 

vernier  to  1 minute 16.00  .35 

1467.  Protractor,  whole  circle,  10-inch,  divided  to  J-  de- 

grees, vernier  to  1 minute 20.00  .50 

1470.  Protractor,  half  circle,  8-inch,  with  horn  center  and 
movable  arm,  divided  to  J degrees,  vernier  to  1 

minute,  with  clamp  and  tangent  to  arm 18.00  .30 

1473.  Protractor,  whole  circle,  8-inch,  with  horn  center 
and  movable  arm,  divided  to  J degrees,  vernier  to 
1 minute,  with  clamp  and  tangent  to  arm 20.00  .40 

MAHOGANY  CASES  FOR  PROTRACTORS. 

1476.  Case  for  Protractors  Nos.  1454,  1455,  1460 $1.75  $0.25 

1477.  Case  for  Protractors  Nos.  1461,  1462,  1465,  1470...  2.25  . .35 

1478.  Case  for  Protractors  Nos.  1466,  1467,  1473 3.00  .45 


LIMB  - PROTRACTOR. 

BRONZE  HEAD,  STEEL  BLADE,  VERNIER  TO  ONE  MINUTE. 
Made  by  W.  & L.  E.  Gurley. 


330 


W.  & L.  E.  GURLEY,  TROY,  N.  K 


LIMB-PROTRACTOR. 


No. 

1480. 

1481. 

1482. 

1483. 

1484. 


BRONZE  HEAD,  STEEL  BLADE,  VERNIER  TO  ONE  MINUTE. 


Limb- Protractor,  with  blade  24-inch. 
Limb- Protractor,  with  blade  30-inch. 
Limb- Protractor,  with  blade  36-inch. 
Limb- Protractor,  with  blade  42-inch. 
Limb- Protractor,  with  blade  48-inch. 


Price. 

Nickel-plated  $8.00 
Nickel-plated  8.75 
Nickel-plated  9.50 
Nickel-plated  10.25 
Nickel-plated  11.50 


Post. 

$0.65 

.70 

.75 

.85 

1.00 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 


331 


No.  Price.  Post. 

1486.  Steel  Protractor,  divided  to  1 degree,  vernier  to 
5 minutes,  8J-inch  blade.  It  is  used  with  the 
T-rule  or  straight-edge.  Very  handy  in  dividing 
circles,  transferring  angles,  laying  off  angles  each 
side  of  a line  without  resetting.  In  morocco  case  $7.75  $0.35 

1488.  German  Silver  Protractor,  8- inch,  half  circle,  half 

degrees,  vernier  to  1 minute.  In  mahogany  case..  40.00  .70 

The  Crozet  Protractor  we  can  recommend  as  the  best 
among  the  high-grade  protractors. 

It  is  used  with  the  T-rule  or  straight-edge.  The  feather- 
edge  is  set  to  the  starting-point  and  lines  produced  without 
puncturing  the  paper. 

DUFFIELD’S  PATENT  PROTRACTOR. 

(Made  by  W.  & L.  E.  Gurley.) 

Made  of  transparent  celluloid,  and  with  two  parallel  scales  of  twenty 
parts  to  the  inch,  to  enable  the  zero  line  to  be  set  parallel  to  meridian 
lines  drawn  on  the  paper. 


1490.  Protractor,  half  circle,  6-inch,  divided  to  \ degrees..  $3.00  $0.12 

1492.  Protractor,  half  circle,  9-inch,  divided  to  J degrees..  3.50  .15 

1494.  Protractor,  half  circle,  12-inch,  divided  to  \ degrees  4.00  .20 

GERMAN  SILVER  PROTRACTORS. 

1500.  German  Silver  Protractor,  4-inch,  half  circle,  whole 

degrees $0.50  $0.03 

1502.  German  Silver  Protractor,  5-inch,  half  circle,  half 

degrees 85  .05 

1503.  German  Silver  Protractor,  6-inch,  half  circle,  half 

degrees 


1.00 


.07 


332 


W.  &•  L.  E.  GURLEY,  TROY,  N.  Y. 


No. 

1509. 

German  Silver  Protractor, 
beveled  edge,  half  degrees. 

5-inch,  half 

circle, 

Price. 

$1.25 

Post. 

$0.13 

1510. 

German  Silver  Protractor, 
beveled  edge,  half  degrees. 

6-inch,  half 

circle, 

1.50 

.15 

1511. 

German  Silver  Protractor, 
beveled  edge,  half  degrees. 

7-inch,  half 

circle, 

2.00 

.18 

BRASS  PROTRACTORS. 


1515.  Brass  Protractor,  3-inch,  half  circle,  whole  degrees 

1516.  Brass  Protractor,  4-inch,  half  circle,  whole  degrees 

1517.  Brass  Protractor,  4-inch,  half  circle,  half  degrees... 

1518.  Brass  Protractor,  5-inch,  half  circle,  half  degrees... 

1519.  Brass  Protractor,  6-inch,  half  circle,  half  degrees... 


$0.10  $0.02 

.20  .03 

.35  .03 

.50  .05 

.60  .07 


HARD  RUBBER  PROTRACTORS. 

1525.  Rubber  Protractor,  6-inch,  half  circle,  half  degrees  $3.00  $0.13 

1526.  Rubber  Protractor,  8-inch,  half  circle,  half  degrees  3.75  .15 

1528.  Rubber  Protractor,  6 -inch,  whole  circle,  half  de- 
grees  3.75  .18 


TRANSPARENT  CELLULOID  PROTRACTORS. 


1532.  Celluloid  Protractor,  6-inch,  half  circle,  beveled 

edge,  half  degrees $3.00  $0.13 

1533.  ^ Celluloid  Protractor,  8 -inch,  half  circle,  beveled 

edge,  half  degrees 3.75  .15 

1535.  Celluloid  Protractor,  6-inch,  whole  circle,  beveled 

edge,  half  degrees 3.75  ,18 


W.  <5r*  L.  E.  GURLEY,  TROY,  N.  Y 


333 


No. 

1540. 

1541. 

1542. 
1544. 

1547. 

1548. 


TRANSPARENT  HORN  PROTRACTORS. 

Price. 

Horn  Protractor,  4-inch,  half  circle,  whole  degrees  $0. 12 

Horn  Protractor,  5-inch,  half  circle,  half  degrees...  .20 

Horn  Protractor,  6-inch,  half  circle,  half  degrees...  .25 

Horn  Protractor,  8-inch,  half  circle,  half  degrees...  .50 

Horn  Protractor,  5-inch,  whole  circle,  half  degrees  1.25 

Horn  Protractor,  6-inch,  whole  circle,  half  degrees  1.50 


Post. 

10.02 

.02 

.03 

.05 

.12 

.14 


1550. 


1550.  Railroad  Curve -Protractor,  of  horn,  8-inch,  half 
circle,  half  degrees,  having  laid  off  on  it  twenty- 
three  curves  from  \ degree  to  8 degrees,  to  a 
scale  of  400  feet  to  the  inch 1.60  .13 


PAPER  PROTRACTORS. 


1552.  Protractor,  on  Bristol -Board,  5-inch,  half  circle, 

half  degrees 

1553.  Protractor,  on  Bristol- Board,  6-inch,  half  circle, 

half  degrees 

1554.  Protractor,  on  Bristol- Board,  5-inch,  half  circle, 

half  degrees,  and  diagonal  scale  to  inches  and 
yi^th,  and  millimeter 

1555.  Protractor,  on  Bristol- Board,  8-inch,  whole  circle, 

half  degrees 

1556.  Protractor,  on  Bristol- Board,  13-inch,  whole  circle, 

quarter  degrees 

1558.  Protractor,  on  Drawing-Paper,  13-inch,  whole  cir- 

cle, quarter  degrees 

1559.  Protractor,  on  Tracing  Paper,  13- inch,  whole  cir- 

cle, quarter  degrees 


$0.10  $0.02 

.15  .02 

.15  .02 

.20  .04 

.40  .07 

.30  .06 

,25  .06 


334 


W.  &■  L.  E.  GURLEY , TROY,  TV  K 


SCALES. 


IVORY  PROTRACTOR-SCALES. 


No.  Price.  Post. 

1560.  Ivory  Rectangular  Protractor,  6 inches  long,  If 

inches  wide,  writh  scales  as  follows  : front  sides 

divided  around  edges  from  0 to  180  degrees  in 
single  degrees,  scales  of  f , f , f and  1 inch  to  the 
foot,  and  scale  of  chords.  Reverse  side  scales  of 
30,  35,  40,  45,  50  and  60  parts  to  the  inch,  scale 
of  chords  and  diagonal  scale  of  inches  and  yl^ths..  §1.50  $0.12 

1561.  Ivory  Rectangular  Protractor,  6 inches  long  by  If 

inches  wide,  with  scales  as  follows  : front  side, 
the  edge  divided  into  single  degrees  from  0 to  180 
degrees,  scales  of  f , J , f,  f , f , f , f,  and  1 inch 
to  the  foot,  and  scale  of  chords.  On  the  reverse 
side,  scales  of  30,  35,  40,  45,  50  and  60  parts  to 
the  inch,  scale  of  chords  and  diagonal  scale  of 
^ths 2.00  .12 

1563.  Ivory  Rectangular' Protractor,  6 inches  long  by  2 

inches  wide,  with  scales  as  follows  : front  side 
the  edge  divided  in  f degrees  from  0 to  180  de- 
grees, scales  of  f , f , f , f , f , f , f,  1,  If,  If  inches 
to  the  foot,  scale  of  chords,  and  line  of  40  parts 
on  lower  edge.  On  the  reverse  side,  scales  of  20, 

25,  30,  35,  40,  45,  50  and  60  parts  to  the  inch, 

and  diagonal  scale  of  yfoths 4.00  .13 

1564.  Ivory  Rectangular  Protractor,  6 inches  long  by  2J 

inches  wide,  with  scales  as  follows : front  side, 
the  edge  divided  in  f degrees  from  0 to  180  de- 
grees, scales  of  f,  f,  f,  f,  f,  f,  f,  1,  If,  If,  If, 

If  inches  to  the  foot,  scale  of  chords,  and  scale 
of  40  parts  on  the  lower  edge.  Reverse  side, 
scales  of  10,  15,  20,  25,  30,  35,  40,  45,  50  and 
60  parts  to  the  inch,  and  diagonal  scale  of  yf^ths  4.50  .13 


W.  &>  L.  E.  GURLEY,  TROY,  N.  Y 


335 


FLAT  BOXWOOD  AND  IVORY  SCALES. 


No.  Price.  Post. 

1570.  Boxwood  Protractor,  6 inches  long,  If  inches  wide, 
divided  to  whole  degrees,  with  scales  J,  J,  f,  1 

inch,  diagonal  scale  and  scale  of  chords $0.35  $0.03 

1572.  Boxwood  Scale,  6-inch,  for  school  use 15  .02 


1573.  Ivory  Scale,  6 -inch,  with  diagonal  and  chain-scales  .75  .03 

1575.  Boxwood  Sector-Scale,  6-inch,  opens  to  12-inch 1.00  .12 

1576.  Ivory  Sector-Scale,  6-inch,  opens  to  12-inch 2.25  .15 

1577.  Boxwood  Scale,  6-inch,  divided  J,  f,  J,  1 inch  to 

the  foot 50  .03 


pT.  .\  ,\  v.  i 

^ i'S  2.0  \ * ® ® \ \ 

1 Hy2  -10  9 8 

ENGINE  DIVIDED  1 

0 55  * 9 9 0T  ZT  IT  i 

| 1 O -| 

xr.s.si. 

i 8S  OV  55V  VV  ST;  94 

lmUS / 06/88  jsa  IW  1 28 1 08  / 8L  / 3L  / U l8L  / OL  1 89  / 99  / 69  M 

IF  ill#  / / / / / / / / / / / / / / / / / //  / / / / / / / / / / /? 

’irinrimiiirnitii 

■ 

1578. 

• 

1578. 

Boxwood  Scale,  12-inch,  divided  J,  f , J,  1 inch  to 
the  foot 

.75 

.06 

1579. 

Boxwood  Scale,  18-inch,  divided  J,  J , J,  1 inch  to 
the  foot 

1.50 

.18 

1580. 

Boxwood  Scale,  24-inch,  divided  J,  f , J,  1 inch  to 
the  foot 

2.00 

.22 

1581. 

Ivory  Scale,  6-inch,  divided  J,  J,  \,  1 inch  to  the 

foot 

2.00 

.12 

1582. 

Ivory  Scale,  12-inch,  divided  J,  J,  J,  1 inch  to  the 
foot 

3.00 

.14 

1583. 

Boxwood  Scale,  6-inch,  divided  f , f , 1J,  3 inches  to 
the  foot 

.50 

.03 

336 


IV.  & L.  £.  GURLEY,  TROY,  N.  Y. 


No.  Price.  Post, 

1584.  Boxwood  Scale,  12-inch,  divided  f,  f , 1J,  3 inches 

to  the  foot |0.75  $0.06 

1585.  Boxwood  Scale,  18-inch,  divided  #,  §,  14,  3 inches 

to  the  foot 1.50  .18 

1586.  Boxwood  Scale,  24-inch,  divided  f,  14,  3 inches 

to  the  foot 2.00  .22 

1587.  Ivory  Scale,  6-inch,  divided  f,  J,  1J,  3 inches  to 

the  foot 2.00  .12 

1588.  Ivory  Scale,  12-inch,  divided  f,  f,  1J,  3 inches  to 

the  foot 3.00  .14 

1590.  Boxwood  White-Edge  Scale,  6-inch,  divided  J,  J, 

J,  1 inch  to  the  foot 75  .03 

1591.  Boxwood  White-Edge  Scale,  12-inch,  divided  J,  J, 

J,  1 inch  to  the  foot 1.25  .14 

1594.  Boxwood  White-Edge  Scale,  6-inch,  divided  f,  f, 

1J,  3 inches  to  the  foot 75  .03 

1595.  Boxwood  White-Edge  Scale,  12-inch,  divided  f,  f, 


1600.  Boxwood  Scale,  12-inch,  with  12  scales,  as  follows  : 

h T6>  h !>  b b 2 and  3 inches  to 

the  foot,  the  first  division  of  each  scale  subdivided 

into  12  parts,  and  diagonal  scale  reading  to 

and  2^0  °f  an  90  .06 

1601.  Ivory  Scale,  12-inch,  divided  same  as  No.  1600 3.00  .14 

1604.  Boxwood  Scale,  12-inch,  one  side  rounded,  the 

other  flat,  with  the  following  scales,  the  gradua- 
tions of  which  are  all  brought  to  the  edge  : 

A,  b t.  h I,  1 b b U,  If,  2,  2£  and  3 
inches  to  the  foot,  the  first  division  of  each  scale 
subdivided  into  12  parts 90  .06 

1605.  Ivory  Scale,  12-inch,  divided  same  as  No.  1604 3.00  .14 

1608.  Boxwood  Scale,  12-inch,  with  diagonal  and  Gunter 

• . scales 75  .06 

1610.  Boxwood  School  Rule,  12-inch,  divided  yL  and  J 

of  an  inch 10  .03 

1611.  Boxwood  School  Rule,  18-inch,  divided  ^ of  an 

inch,  and  with  inlaid  brass  edges 35  .10 

1612.  School  Rule,  12-inch,  beveled  edges,  divided  ^ of 

an  inch  and  millimeters 15  .05 

1613.  School  Rule,  18-inch,  beveled  edges,  divided  ^ of 

an  inch  and  millimeters 35  .10 


W.  & Z.  E.  GURLEY,  TROY,  N.  K 


337 


FLAT  BOXWOOD  CHAIN  - SCALES. 


1 12  11  10  9 | 

! iol 

ENGINE  DIVIDED  < 

| 0 Z + 9 8 0!  ZT  *1  91  81  i 

1 2 1 0 
m us.  sd 

i OS  2S  tS  9S  BS  09 

1618. 


No. 

1615. 

1616. 

1617. 

1618. 

1619. 

1620. 
1627. 
1632. 
1C33. 
1634. 
1641. 


Boxwood  Scale,  6-inch,  divided  10  and  50  parts  to 

the  inch 

Boxwood  Scale,  6 -inch,  divided  20  and  40  parts  to 

the  inch 

Boxwood  Scale,  6-inch,  divided  30  and  60  parts  to 

the  inch 

Boxwood  Scale,  12-inch,  divided  10  and  50  parts  to 

the  inch 

Boxwood  Scale,  12-inch,  divided  20  and  40  parts  to 

the  inch 

Boxwood  Scale,  12-inch,  divided  30  and  60  parts  to 

the  inch 

Boxwood  Off-set  Scales,  2-inch,  divided  like  Nos. 

1615  to  1617,  each 

Boxwood  White- Edge  Scale,  12 -inch,  divided  10 

and  50  parts  to  the  inch 

Boxwood  White-Edge  Scale,  12-inch,  divided  20 

and  40  parts  to  the  inch 

Boxwood  White-Edge  Scale,  12-inch,  divided  30 

and  60  parts  to  the  inch 

White-Edge  Off-set  Scales,  2-inch,  divided  like 
Nos.  1632  to  1634,  each 


Price- 

Post. 

$0.50 

$0.03 

.50 

.03 

.50 

.03 

.75 

.06 

.75 

.06 

.75 

.06 

.40 

.02 

1.25 

.14 

1.25 

.14 

1.25 

.14 

.70 

.02 

FLAT  METALLIC'  CHAIN- SCALES. 

(A  superior  article,  our  own  make,  made  of  brass,  and  nickel-plated. 
Divided  on  beveled  edges. ) 

1645.  Flat  Metal  Scale,  12-inch,  divided  10  and  50  parts 

to  the  inch $3.00  $0.18 

1646.  Flat  Metal  Scale,  12-inch,  divided  20  and  40  parts 

to  the  inch 3.00  .18 

1647.  Flat  Metal  Scale,  12-inch,  divided  30  and  60  parts 

to  the  inch 3.75  .18 

Flat  Metal  Scale,  12-inch,  divided  80  and  100  parts 
to  the  inch 


1648. 


5.00 


.18 


338 


IV.  L.  E.  GURLEY,  TROY,  N.  Y. 


No.  Price.  Post. 

1649.  Flat  Metal  Scale,  12-inch,  divided  100  and  500 

parts  to  the  foot $3.00  $0.18 

1650.  Flat  Metal  Scale,  30  centimeters,  divided  to  milli- 

meters and  half  millimeters  3.75  .18 


% 

TRIANGULAR  BOXWOOD  SCALES.  € 


1655.  Triangular  Boxwood  Scale,  6-inch,  divided  T3g, 

if  if  if  if  if  and  3 inches  to  the  foot,  and 

one  edge  inches  and  l'6ths $0.75  $0.04 

1656.  Triangular  Boxwood  Scale,  12-inch,  divided  J,  J, 

f,  if  if  1J,  2,  3 and  4 inches  to  the  foot,  and 

one  edge  inches  and  16ths 1.00  .14 

1657.  Triangular  Boxwood  Scale,  18-inch,  divided  J,  J, 

f,  if  f>  1>  1J,  2,  3 and  4 inches  to  the  foot,  and 

one  edge  inches  and  16ths 2.50  .20 

1658.  Triangular  Boxwood  Scale,  24-inch,  divided  J,  J, 

-§,  if  1)  2,  3 and  4 inches  to  the  foot,  and 

one  edge  inches  and  16ths 4.25  .25 


1660.  Triangular  Boxwood  Scale,  6 -inch,  divided  10,  20, 


30,  40,  50  and  60  parts  to  the  inch 75  .04 

1661.  Triangular  Boxwood  Scale,  12-inch,  divided  10,  20, 

30,  40,  50  and  60  parts  to  the  inch 1.00  .14 

1662.  Triangular  Boxwood  Scale,  18-inch,  divided  10,  20, 

30,  40,  50  and  60  parts  to  the  inch 2.50  .20 

1663.  Triangular  Boxwood  Scale,  24-inch,  divided  10,  20, 

30,  40,  50  and  60  parts  to  the  inch 4.25  .25 


IV.  fir-  L.  E.  GURLEY,  TROY,  N.  Y.  339 

No.  Price.  Post. 

1665.  Triangular  Boxwood  Scale,  12-inch,  divided  20,  30, 

40,  50,  60  and  80  parts  to  the  inch $1.00  $0.14 

1668.  Triangular  Off-set  Scale,  2-inch,  divided  same  as 

No.  1660 60  .02 

1670.  Triangular  Boxwood  Scale,  12-inch,  divided  100, 

200,  300,  400,  500  and  600  parts  to  the  foot 1.50  .14 


TRIANGULAR  BOXWOOD  SCALES  WITH  WHITE 

EDGES. 


1674.  White-Edge  Scale,  6-inch,  divided  same  as  No. 

1655  $1.50  $0.11 

1675.  White-Edge  Scale,  12-inch,  divided  same  as  No. 

1656  ....: 

1678.  White-Edge  Scale,  6-inch,  divided  same  as  No. 

1660  

1679.  White-Edge  Scale,  12-inch,  divided  same  as  No. 

1660  . 

1682.  White-Edge  Scale,  12-inch,  divided  same  as  No. 

1665  

1684.  White-Edge  Scale,  12-inch,  divided  same  as  No. 

1670  


$1.50 

$0.11 

2.50 

.14 

1.50 

.11 

2.50 

.14 

2.50 

.14 

2.50 

.14 

METALLIC  TRIANGULAR  SCALES. 


The  Metallic  Triangular  Scales  are  made  of  brass  tubing  with  the 
ends  closed,  nickeled  with  a dull  finish,  and  weigh  about  three  and  one- 
half  ounces. 

The  liability  of  the  wood  scales  to  crack,  warp,  or  twist,  the  chipping 
of  their  edges,  and  their  variation  from  standard  measurement,  are  well 
known  to  all  who  have  used  them.  These  objections  have  been  over- 
come in  the  metallic  scale. 


1690.  Metallic  Triangular  Scale,  12-inch,  divided  same  as 

No.  1656 $2.50  $0.16 

1692.  Metallic  Triangular  Scale,  12-inch,  divided  same  as 

No.  1660 2.50  .16 

1694.  Metallic  Triangular  Scale,  12-inch,  divided  same  as 

No.  1665 2.50  .16 

1698.  Guard  for  Triangular  Scale  (preventing  all  errors)..  .20  .02 


340  w.  & L.  E.  GURLEY \ TROY,  N.  Y. 

METRIC  SCALES  AND  RULES. 


No.  Prick.  Post. 

1700.  Flat  Boxwood  Scale,  20  centimeters,  divided  to 

millimeters  and  J millimeters $0.60  $0.04 

1701.  Flat  Boxwood  Scale,  30  centimeters,  divided  to 

millimeters  and  J millimeters 75  .06 

1702.  Flat  Boxwood  Scale,  50  centimeters,  divided  to 

millimeters  and  J millimeters 1.50  .18 

1703.  Flat  White-Edge  Scale,  20  centimeters,  divided  to 

millimeters  and  J millimeters 1.00  .12 

1704.  Flat  White-Edge  Scale,  30  centimeters,  divided  to 

millimeters  and  J millimeters 1.25  .14 

1706.  Triangular  Boxwood  Scale,  20  centimeters,  divided 

to  .01,  .02,  .03,  .05,  .025,  .0125 1.25  .12 

1707.  Triangular  Boxwood  Scale,  30  centimeters,  divided 

to  .01,  .02,  .03,  .05,  .025,  .0125 1.50  .14 

1710.  Triangular  Boxwood  Scale,  30  centimeters,  divided 
to  millimeters  and  J millimeters,  also  to  lOths, 

12ths  and  16ths  of  inches,  and  lOOths  of  a foot ...  2.00  .14 

1712.  Triangular  White-Edge  Scale,  30  centimeters, 

divided  same  as  No.  1706 2.50  .14 

1714.  Triangular  White-Edge  Scale,  30  centimeters 

divided  same  as  No.  1710 3.00  .14 

1718.  Flexible  Wood  Rule,  four  feet,  eight  fold,  divided  to 
millimeters  and  16ths  of  inches,  and  with  spring 
joints 50  .05 


PAPER  SCALES. 

1724.  Paper  Scale,  lj-inch  wide,  12  inches  long,  gradua- 
tions on  one  edge  inches  and  lOths,  and  the  other 


feet  and  lOOths $0.10  $0.02 

1725.  Paper  Scale,  same  as  1724,  edges  20  and  40  parts  to 

the  inch .*. 10  .02 

1726.  Paper  Scale  same  as  1724,  edges  16  and  48  parts  to 

the  inch 10  .02 

Paper  Scales,  printed  on  card-paper,  19  inches  long, 
for  architects  and  engineers,  as  follows  : 

1727.  Series  A contains  6 scales,  one  each  divided  to  J,  J, 

f,  1,  1J,  and  3 inches  to  the  foot,  each  scale 20  .04 

1728.  Series  B contains  6 scales,  one  each  divided  ^3¥,  J, 

f,  and  f inches  to  the  foot,  each  scale 20  .04 

1729.  Series  C contains  6 scales,  one  each  divided  to  10, 

20,  30,  40,  50  and  60  parts  to  the  inch,  each  scale  .20  .04 


IV.  &°  L.  E.  GURLEY,  TROY,  N.  Y. 


341 


THACHER’S  CALCULATING-INSTRUMENT. 

No.  • Price. 

1730.  Thacher’s  Calculating-Instrument,  with  cylinder  18 
inches  long.  Performs  a great  variety  of  useful 
calculations  with  rapidity  and  accuracy.  In  ma- 
hogany box  and  with  instruction  book $ 35.00 

BOXWOOD  AND  IVORY  POCKET-RULES,  Etc. 

No.  Price.  Post. 

1735.  Boxwood  Rule,  one  foot,  fourfold,  8ths  and  16ths 

of  inches  $0.10  $0.03 

1736.  Boxwood  Rule,  one  foot,  four  fold,  edge-plates,  8ths 

and  16ths  of  inches 18  .03 

1737.  Boxwood  Rule,  one  foot,  four  fold,  brass  edges, 

bound,  8ths  and  16ths  of  inches 30  .04 

1740.  Boxwood  Rule,  two  feet,  four  fold,  8ths  and  16ths 

of  inches 15  .05 

1741.  Boxwood  Rule,  two  feet,  four  fold,  edge-plates,  8ths, 

lOths,  12ths  and  16ths  of  inches,  and  drafting- 

scales 25  .05 

1742.  Boxwood  Rule,  two  feet,  four  fold,  brass  edges, 

bound,  8ths,  lOths,  12ths  and  16ths  of  inches,  and 

drafting  scales 50  .06 

1743.  Boxwood  Rule,  two  feet,  fourfold,  edge-plates,  8ths, 

lOths,  12ths  and  16ths  of  inches,  and  drafting- 

scales,  and  inside  beveled  edges 50  .06 

1745.  Boxwood  Caliper- Rule,  one  foot,  four  fold,  edge- 

plates,  8ths,  lOths,  12ths  and  16ths  of  inches 40  .04 

1747.  Ivory  Rule,  one  foot,  four  fold,  edge-plates,  8ths, 

lOths,  12ths  and  16ths  of  inches 1.40  .12 

1748.  Ivory  Rule,  one  foot,  four  fold,  edge-plates,  8ths, 

lOths,  12ths  and  16ths  of  inches  and  lOOths  of  a 

foot 1.85  .12 

1749.  Ivory  Rule,  one  foot,  four  fold,  German  silver  edges, 

bound,  divided  like  No.  1748 2.50  .13 

1750.  Ivory  Caliper- Rule,  one  foot,  four  fold,  edge -plates, 

divided  like  No.  1748 2.15  .13 

1751.  Ivory  Caliper- Rule,  one  foot,  four  fold,  German 

silver  edges,  bound,  divided  like  No.  1747 2.85  .13 

1753.  Ivory  Rule,  two  feet,  four  fold,  edge-plates,  8ths, 

lOths,  12ths  and  16ths  of  inches,  and  lOOths  of  a 

foot.. 4.25  .15 

1754.  Ivory  Rule,  two  feet,  four  fold,  German  silver  edges, 

bound,  8ths,  lOths,  12ths  and  16thsof  inches,  and 

drafting -scales 5.00  .15 


342  W.  L.  £.  GURLEY,  TROY,  N.  Y. 


No.  Price.  Post. 

1755.  Flexible  Wood  Rule,  four  feet,  eight  fold,  divided 

to  16ths  of  an  inch  and  lOOths  of  a foot,  with 

spring  joints $0.50  $0.05 

1756.  Flexible  Wood  Rule,  four  feet,  eight  fold,  divided 

to  16ths  of  inches,  and  with  spring  joints 50  .05 

1757.  Flexible  Wood  Rule,  four  feet,  eight  fold,  divided 

to  16ths  and  20ths  of  inches,  and  with  spring  joints,  .50  .05 

1758.  Boxwood  Shrink- Rule,  divided  to  8ths,  lOths,  12ths 

and  16ths  of  inches.  Either  24^,  24 24|  or 

24 J = 24  inches.  Each  style 1.20  .18 


1760.  Boxwood  Combination  Rule,  one  foot,  two  fold. 

It  combines  in  itself  a Carpenter’s  Rule, 

Spirit-Level,  Square,  Plumb,  Bevel,  Indicator, 

Brace-Scale,  Drafting-Scale  of  equal  parts, 

T-Square,  Protractor,  Right-angle  Triangle,  and 
with  a straight-edge  can  be  used  as  a Parallel 
Ruler n 2.00  .15 


BOXWOOD  SLIDE-RULES.  (See  page  3^3.) 


1762.  Faber’s  Slide-Rule  and  Calculating-Scale,  lOJ-inch, 

with  glass  indicator  and  directions $3.75  $0.20 

1763.  Students’  Slide-Rule  (for  beginners),  10-inch,  with 

indicator  and  directions 1.00  .15 

1764.  Engineers’  Slide-Rule  (Mannheim),  10-inch, 

divided  on  white  facings,  with  glass  indicator 

and  directions 4.50  .15 

1765.  Duplex  Slide-Rule,  10-inch,  divided  on  white  fac- 

ings, with  brass  indicator,  Arithmetical  slide  and 

directions 6.50  .15 

1767.  Duplex  Slide-Rule,  10-inch,  divided  on  white  fac- 

ings, with  brass  indicator  and  both  Arithmetical 

and  Trigonometrical  slides  and  directions 8.00  .20 

1768.  Stadia  Slide-Rule,  20-inch,  divided  on  white  fac- 

ings. This  rule  is  designed  to  solve  the  equa- 
tions generally  used  in  stadia  measurements 12.50  .35 

1769.  Engineers’  Slide-Rule  (Mannheim),  20-inch, 

divided  on  white  facings,  with  glass  indicator 

and  directions 12.50  .35 

The  Slide-Rule  Manual,  by  Wm.  Cox 50 

Manual  of  The  Duplex  and  Mannheim  Slide-Rules...  .75 

Manual  of  The  Slide-Rule,  by  F.  A.  Halsey 50 

Explanation  of  The  Mannheim  Slide-Rule,  by  C. 

W.  Crockett 75 


NQ'57 


343 


W.  &•  L.  E.  GURLEY , TROY,  N.  Y. 


1762.  1764. 

(For  prices,  see  pages  341  and  342.) 


1760 


344 


W.  & L.  E.  GURLEY,  TROY , M Y. 


STANDARD  STEEL  RULES. 


No. 

Price. 

Post. 

No. 

Price. 

Post. 

1770. 

3-inch — 

$0.35 

$0.02 

1775. 

18-inch 

$2.00 

$0.20 

1772. 

6 “ .... 

65 

.05 

1776. 

24  “ .... 

2.75 

.30 

1774. 

12  “ .... 

1.25 

.15 

1777. 

36  “ .... 

7.00 

.50 

These  rules  are  divided  on  four  edges  in  parts  of  inches  as  follows  : 
10,  20,  50,  100  ; 12,  24,  48  ; 16,  82,  64  ; 8. 


STANDARD  METRIC  STEEL  RULES. 


1780.  TV-meter $0.45  $0.03 

1781.  a “ 85  .14 

1782.  T30  “ 1.25  .16 

These  rules  are  divided  on  three 
fifths  of  millimeters. 


1783.  i-meter $ 2.00  $0.22 

1784.  1 “ 8.00  .55 

edges  to  millimeters  and  one  edge  to 


TRIANGULAR  STEEL  RULES. 


1785. 

1785.  3-inch $0.50  $0.03  i 1787.  6-inch $1.00  $0.13 

1786.  4 “ 70  .05  I 1788.  12  “ 2.00  .15 

These  rules  are  divided  on  three  edges  in  parts  of  inches  as  follows  : 
20,  50,  100  ; 12,  24,  48  ; 16,  32,  64. 


SQUARE  STEEL  RULES. 


1790. 

1790.  3-inch $0.45  $0.03  i 1792.  6-inch $0.90  $0.13 

1791.  4 “ 60  .05  I 

These  rules  are  divided  on  four  edges  in  parts  of  inches  as  follows  : 
16,  32,  64,  100. 


STEEL  STRAIGHT-EDGES.  (Square  Edges.) 


Nickel- 

Plain.  Plated.  Post. 


1800. 

15-i 

inch..$0.90 

$1.15  $0.15 

1801. 

18 

“ ..  1.00 

1.25 

.18 

1802. 

24 

“ ..  1.50 

1.90 

.24 

1803. 

30 

“ ..  2.25 

2.70 

.30 

Nickel- 

Plain.  Plated.  Post. 


1804. 

36-i 

inch..$3.00  J 

$3.50  $0.40 

1805. 

42 

“ ..  4.00 

4.50 

.50 

1806. 

48 

“ ..  6.00 

6.60 

.65 

1807. 

60 

“ ..  8.00 

8.70 

. .... 

IV.  &>  L.  E.  GURLEY,  TROY,  %N.  K 


345 


STEEL  STRAIGHT-EDGES,  NICKEL-PLATED. 

(One  Edge  Beveled.) 


No. 

Price. 

Post. 

No. 

Price. 

Post. 

1810. 

18-inch.... 

$2.00 

$0.18 

1813. 

36-inch 

$5.00 

$0.40 

1811. 

24-inch 

3.00 

.24 

1814. 

42-inch 

6.50 

.50 

1812. 

30-inch.... 

4.00 

.30 

1815. 

48-inch.... 

8.00 

.65 

MAHOGANY  STRAIGHT-EDGES,  AMBER- LINED. 


(One  Edge  Beveled.) 


1820.  18-inch $0.90  $0.06 

1821.  24-inch 1.10  .16 

1822.  30-inch 1.25  .18 


1823.  36-inch $1.90  $0.25 

1824.  42-inch 2.50  .32 

1825.  48-inch 3.00  .40 


MAHOGANY  STRAIGHT-EDGES,  EBONY -LINED. 

(Square  Edges.) 


1830. 


1830. 

24-inch 

.....$0.50 

$0.08 

1833. 

42-inch 

$1.00 

$0.32 

1831. 

30-inch.... 

60 

.12 

1834. 

48-inch 

1.35 

.40 

1832. 

36 -inch 

80 

.15 

1835. 

60-inch 

2.00 

HARD  RUBBER  STRAIGHT-EDGES. 

(Square  Edges.) 


1840. 


1840. 

18-inch 

$0.50 

$0.06 

1843. 

36-inch 

$1.35 

$0.25 

1841. 

24-inch 

75 

.08 

1844. 

42-inch 

1.75 

.32 

1842. 

30-inch 

1.00 

.18 

1845. 

48-inch — 

2.25 

.40 

346 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y 

HARDWOOD  STRAIGHT-EDGES. 

(One  Edge  Beveled.) 


1850. 


No. 

Price. 

Post. 

No. 

Price. 

Post. 

1850. 

18-inch 

$0.25 

$0.06 

1854. 

42-inch. ... 

$0.50 

$0.24 

1851. 

24-inch 

35 

.08 

1855. 

48-inch 

65 

.32 

1852. 

30-inch 

40 

.12 

1856. 

60-inch 

1.00 

1853. 

36-inch 

45 

.15 

1857. 

72-inch.... 

1.25 

T-SQUARES. 


MAHOGANY  T-SQUARES  WITH  AMBER  EDGES 


1860.  18-inch. 

1861.  24-inch. 

1862.  30-inch. 


.$1.10  $0.*25 
. 1.40  .35 

. 1.90  .45 


1863.  36-inch. 

1864.  42-inch. 

1865.  48-inch. 


,$2.35 
. 2.75 
. 3.35 


).50 

.55 


MAHOGANY  T-SQUARES  WITH  AMBER  EDGES 
AND  SHIFTING  'HEAD. 


1870.  18-inch $1.85  $0.30 

1871.  24-inch 2.25  .40 

1872.  30-inch 2.60  .50 


1873.  36-inch $2.90  $0.55 

1874.  42-inch 3.25  .60 

1875.  48-inch 3.75 


RUBBER  BLADE  T-SQUARES,  HARDWOOD 
HEAD,  FIXED. 


$0.90  $0.25 

1.25  .35 


1882.  30-inch, 

1883.  36-inch, 


1880.  18-inch.. 

1881.  24-inch.. 


.$1.60  $0.45 
. 2.00  .50 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 


347 


RUBBER  BLADE  T-SQUARES,  HARDWOOD 
HEAD,  SHIFTING. 

No.  Price.  Post. 

1888.  18-inch.........  $1.60  $0.30 

1889.  24-inch 2.00  .40 


No. 

1890. 

1891. 


Price.  Post. 

30-inch $2.35  $0.50 

36-inch 2.75  .55 


STEEL  BLADE  T-SQUARES,  NICKEL-PLATED, 
WITH  FIXED  JAPANNED  IRON  HEAD. 


1896.  18-inch. 

1897.  24-inch. 


13.00  $0.35 
3.50  .'40 


1898.  30-inch $4.50  $0.45 

1899.  36-inch 5.50  .50 


STEEL  BLADE  T-SQUARES,  NICKEL-PLATED, 
WITH  SHIFTING  JAPANNED  IRON  HEAD. 


1902.  18-inch. 

1903.  24-inch. 


$4.25  $0.45 
5.00  .50 


1904.  30-inch $5.75  $0.55 

1905.  36-inch 6.75  .60 


HARDWOOD  T-SQUARES,  FIXED  HEAD, 


1908.  15-inch $0.30  $0.15 

1909.  20-inch 40  .25 

1910.  25-inch 45  .35 


1911.  30-inch $0.50  $0.45 

1912.  40-inch 75  .60 

1913.  50-inch 1.00  .... 


HARDWOOD  T-SQUARES,  SHIFTING  HEAD. 


1916.  15-inch $0.80  $0.20 

1917.  20-inch 90  .30 

1918.  25-inch 95  .40 


1919.  30-inch $1.00  $0.50 

1920.  40-inch 1.25  .65 

1921.  50-inch 1.50  .... 


348 


PY.  & L.  E.  GURLEY,  TROY,  N.  Y. 


N°-  Price.  Post. 

1924.  “ R.  P.  I.”  Hardwood  T-Square,  30-inch  blade  with 

beveled  edges,  fixed  curved  head,  superior $1.25  $0.45 

1926.  “ R.  P.  I.”  Hardwood  T-Square,  30-inch  blade  with 

beveled  edges,  shifting  curved  head,  superior 2.00  .50 


T-  SQUARES  WITH  DEANE’S  PATENT  SWIVEL 
AND  ADJUSTMENT. 


1930.  24-inch,  Mahogany  Blade,  Amber  Edges,  Style 

No.  1 $3.65  $0.40 

1931.  30-inch,  Mahogany  Blade,  Amber  Edges,  Style 

No.  1 4.15  .45 

1932.  36-inch,  Mahogany  Blade,  Amber  Edges,  Style 

No.  1 4.75  .50 

1935.  24-inch,  Mahogany  Blade,  Amber  Edges,  Style 

No.  3 3.15  .40 

1936.  30-inch,  Mahogany  Blade,  Amber  Edges,  Style 

No.  3 3.65  .45 

36-inch,  Mahogany  Blade,  Amber  Edges,  Style 
No.  3 , 


1937. 


4.25 


.50 


W.  6-  L.  E.  GURLEY,  TROY,  N.  Y 


349 


DRAWING-TABLES. 


1950. 


No.  Price. 

1950.  Drawing-Table,  hardwood  top,  30x20  inches $7.00 

1953.  Drawing-Table,  ash  top,  24  x 22  inches 8.00 

1954.  Drawing-Table,  ash  top,  24x22  inches,  and  with  instru- 

ment shelf,  24  x 7 inches 9.00 

1956.  Drawing-Table,  black  walnut  top,  26  x 22  inches,  instru- 
ment shelf  26  x 7 inches,  two  instrument  drawers,  orna- 
mented stand 12.00 

1958.  Drawing-Table,  ash  top,  26  x 22  inches,  with  instrument 
shelf  and  two  drawers  and  with  folding  arm  and  plain 
shelf,  ornamented  stand 17.00 


Note. — These  Tables  are  adjustable  for  horizontal  and  angular  motion  and  for 
heights  about  30  to  44  inches.  The  shelves  and  drawers  remain  level  when  the 
top  is  inclined.  They  are  mounted  on  an  iron  stand  with  castors. 


350  W.  & L.  E.  G UK  LEY,  TROY,  N.  Y. 

DRAWING-BOARDS  AND  TRESTLES. 

No.  Price. 

1960.  Drawing-Board,  pinewood,  14  x 10  inches $0.35 

1962.  Drawing-Board,  pinewood,  20x15  inches,  tongue  and 

groove  ends 75 

1964.  Drawing-Board,  pinewood,  28x20  inches,  tongue  and 

groove  ends 1.50 

1966.  Drawing-Board,  pinewood,  40x28  inches,  tongue  and 

groove  ends 2. 50 

1967.  Drawing-Board,  pinewood,  55x33  inches,  dovetailed  cleats 

on  under  side 7.00 

1970.  Drawing-Board,  with  mahogany  frame,  and  removable  pine- 
wood center,  18  x 13  inches 3.00 

1972.  Drawing-Board,  with  mahogany  frame,  and  removable  pine- 
wood center,  25  x 17  inches 4.00 

(Drawing-Boards  and  Trestles  of  any  size  made  to  order.) 

1975.  Pinewood  Horses,  37  inches  high,  35  inches  long,  with  re- 
movable sloping  ledges.  Per  pair 5.00 

1977.  Folding  Trestle,  hardwood,  37  inches  high,  33  inches  long, 

26  inches  wide each  8.00 

1978.  Folding  Trestle,  hardwood,  37  inches  high  combined  with 

adjustable  Drawing-Board  of  pinewood,  42  x 31  inches, 
and  hinged  to  the  Trestle.  All  folding  compactly each  14.00 


IV.  6-  L.  E.  GURLEY,  TROY,  N.  Y. 


351 


TRIANGLES. 


OPEN  STEEL  TRIANGLES.  NICKEL-PLATED. 

30°  x 60a  x 90°. 


No. 

Price. 

Post. 

No. 

Price. 

Post. 

1982. 

6 -inch 

$3.20 

$0.15 

1986.  lOJ-inch... 

....$4.25 

$0.25 

1984. 

8 -inch 

3.85 

.20 

45°  x 45 

1989.  15-inch 

.°  x 90°. 

....  6.50 

.40 

1992. 

6J-inch 

3.50 

.18 

1996.  10-inch 

....  5.50 

$0.35 

1994. 

8-inch 

4.25 

.25 

1998.  12-inch 

....  6.50 

.45 

OPEN  GERMAN  SILVER  TRIANGLES. 

30°  x 60°  x 90°. 


2002. 

6-inch 

$2.50 

$0.15 

2006. 

10-inch 

$4.00 

$0.25 

2004. 

8-inch 

3.00 

.20 

2008. 

12-inch 

5.00 

.30 

45°  x 45°  x 90°. 

2012. 

6-inch 

2.75 

.18 

2016. 

10-inch 

5.00 

.35 

2014. 

8-inch 

4.00 

.25 

2018. 

12-inch 

.....  6.50 

.45 

TRANSPARENT  AMBER  TRIANGLES. 


2036. 

45°  x 45°  x 90°. 


2022. 

30°  x 60°  x 90°. 


(For  prices*  see  page  352.) 


352 


W.  6-  Z.  E.  GURLEY,  TROY,  N.  Y. 


TRANSPARENT  AMBER  TRIANGLES. 


30°  x 60°  x 90°. 


No. 

Price. 

Post. 

No. 

Price. 

Post. 

2022. 

4-inch 

$0.25 

$0.03 

2028. 

10-inch 

....$0.75 

$0.08 

2024. 

6-inch 

40 

.04 

2030. 

12-inch 

....  1.00 

.18 

2026. 

8-inch 

55 

.06 

2032. 

14-inch 

....  1.65 

.20 

45°  x 45°  x 90°. 

2036. 

4-inch 

35 

.04 

2042. 

8-inch 

75 

.08 

2038. 

6-inch 

.05 

2044. 

10-inch 

....  1.10 

.18 

2040. 

7-inch 

65 

.07 

2046. 

12-inch 

....  1.65 

.20 

HARD  RUBBER  TRIANGLES. 


2052.  2074. 

30°  x 60°  x 90°.  45°  x 45°  x 90°. 


30°  X 60°  X 90°. 


2052. 

4-inch 

$0.20 

$0.03 

2058. 

10-inch 

....$0.65 

$0.08 

2054. 

6-inch 

30 

.04 

2060. 

12-inch 

90 

.10 

2055. 

7-inch 

35 

.05 

2062. 

14-inch 

....  1.25 

.20 

2056. 

8-inch. 

45 

.06 

2064. 

16-inch 

....  1.50 

.25 

45°  x 45°  x 90°. 

2074. 

4-inch 

25 

.04 

2078. 

8-inch 

65 

.08 

2075. 

5-inch 

35 

.05 

2080. 

10-inch 

95 

.10 

2076. 

6-inch 

45 

.05 

2082. 

12-inch 

....  1.30 

.20 

2077. 

7-inch 

.07 

2084. 

14-inch 

....  1.85 

.25 

Other  sizes  of  Amber  or  Rubber  Triangles  to  order. 


W.  L.  E.  GURLEY,  TROY,  N.  Y. 


353 


HARDWOOD  TRIANGLES,  OPEN  CENTER, 
FRAMED. 


2108. 

45°  x 45°  x 90° 


30°  X 60°  X 90° 


No. 

2092. 

6-inch 

Price. 
.... |0.20 

Post. 

$0.04 

No. 

2098. 

12-inch 

Price. 

....$0.40 

Post. 

$0.10 

2094. 

8-inch 

25 

.06 

2100. 

14-inch 

50 

.12 

2096. 

10-inch 

30 

.08 

2102. 

16-inch 

60 

.18 

2107. 

5-inch 

20 

45°  x 45 
.05 

»°  x 90° 
2110. 

8-inch 

35 

.08 

2108. 

^6-inch 

25 

.05 

2112. 

10-inch 

40 

.10 

2109. 

7-inch..... 

30 

.08 

2114. 

12-inch 

50 

.12 

HARDWOOD  TRIANGLES,  PLAIN. 


2120. 

2130. 

30°  x 60°  x 90° 

45°  x 45°  x 90° 

• 

30°  x 60°  x 90° 

2120. 

4-inch $0.08 

$0.03 

2124. 

8-inch 

..$0.12 

$0.06 

2122. 

6-inch 10 

.04 

2126. 

10-inch 

..  .15 

.08 

45°  x 45°  x 90° 

2130. 

4-inch 10 

.04 

2132. 

6 -inch 

..  .15 

.05 

2131. 

5-inch 12 

.05 

2134. 

8-inch 

„ ,18 

.08 

354 


W.  df  L.  E.  GURLEY,  TROY,  N.  Y. 


HARD  RUBBER  LETTERING  TRIANGLES. 


2140. 


No.  Price.  Post. 

2140.  Lettering  Triangles  for  Block  Letters,  3J-inch,  three 

in  a set.  Per  set $1.35  $0.12 


2145. 


k 


ixyr 

T R Q V , N 

2145.  Lettering  Triangles  for  Shaded  Letters,  3J-inch, 

three  in  a set.  Per  set 1.20  .12 

2146.  Hard  Rubber  Lettering  Templets,  three  in  a set. 

Per  set 1.50  .15 

2147.  Transparent  Amber  Lettering  Templets,  three  in  a 

set.  Per  set 2.00  .15 


HARD  RUBBER  TRIANGLES  FOR  EMBANK- 
MENTS AND  ROOF  PITCHES. 

2150,  Rubber  Triangles,  for  slopes  J to  1,  J to  1,  f to  1, 

1 to  1,  1^  to  1,  1|  to  1,  2 to  1,  Per  set  of  seven  $2,50  $0.16 


IT.  & L.  E.  GURLEY, , TROY,  N.  Y. 
SECTION-LINERS. 


355 


This  Section-Liner  is  positive  in  all  its  motions,  being  operated  by  a 
rack  and  pinion  movement.  The  rack-rod  passes  through  two  heavy 
weights  and  is  held  securely  by  clamp-screws.  Two  nee^T°»n^d  Pins 
aid  to  hold  the  weights  in  place  when  necessary  Lines  can  be  drawn  at 
any  angle,  in  any  direction,  and  on  any  part  of  the  board. 


356 


W.  & L.  E.  GURLEY,  TROY,  N.  Y. 


SECTION-LINERS  ( Concluded ). 

No.  Price. 

2155.  Section-Liner  with  12-inch  rack  and  12-inch  blade $6.50 

2156.  Section-Liner  with  14-inch  rack  and  14-inch  blade 7.50 

Longer  blades  to  order. 


Each  of  these  Section-Liners  is  packed  in  neat  case  with  printed 
directions  for  use. 

Two  plain  notched  wheels  are  furnished  with  each  instrument  r 
for  producing  64  and  100  parts  to  the  inch.  Extra  wheels  for  either 
10,  12,  20,  24,  40,  48  and  50  parts  to  the  inch  will  be  furnished  for 
$1.50  each.  These  notched  wheels  when  graduated  on  the  face  for 
ruling  and  measuring  combined  will  cost  $2.25  each. 


NO.  2168. 


No.  Price.  Post. 

2168.  Marion’s  Section-Liner  with  7-inch  triangle  and 

10-inch  ruler $2.00  $0.20 

2170.  Standard  Section-Liner.  Especially  adapted  for 

school  use  and  mechanical  sectional  drawing 1.50  .20 

2172.  Bergner’s  Section-Liner 7.50  .30 

2175.  Terry’s  Positive  Section-Liner  with  12-inch  ruler 

and  brace  attachment 10.00 

2177.  Both’s  Section-Liner  and  Scale-Divider,  with  14f- 
inch  base,  9-inch  rack,  arm  10-inch  beyond 
protractor 12.00  .40 


357 


IV.  & L.  E.  GURLEY,  TROY,  N.  V. 

IRREGULAR  CURVES  OF  HARD  RUBBER 
AMBER  AND  WOOD. 


NOS.  2180,  2182  AND  2104. 


358 


W.  & L.  E.  GURLEY,  TROY,  N.  Y. 


IRREGULAR  CURVES  OF  HARD  RUBBER, 
AMBER  AND  WOOD. 


(See  patterns  on  page  351.) 

No,  Prick.  Post. 

2180.  Hard  Rubber  Curves,  Nos  1,  2,  14.  16,  17,  22,  25 

and  26.  Each $0.35  $0.03 

Hard  Rubber  Curves,  Nos.  5,  15,  18,  21  and  23. 

Each 40  .03 

Hard  Rubber  Curves,  Nos.  3,  4,  13,  19,  20  and  24. 

Each ,50  .05 

Hard  Rubber  Curve,  No.  27 75  .08 

Hard  Rubber  Curve,  No.  28 2.25  .18 

Hard  Rubber  Curve,  Logarithmic  Spiral,  No.  29...  1.50  .13 

2182.  Transparent  Amber  Curves,  Nos.  1,  2,  5,  16,  22,  25 

and  26.  Each 45  .03 

Transparent  Amber  Curves,  Nos.  3,  4,  13,  19  and 

20.  Each 60  .05 

Transparent  Amber  Curve,  No.  24 75  .05 

Transparent  Amber  Curve,  No.  27 90  .08 

2184.  Wood  Curves,  Nos.  1,  5,  21,  25  and  26.  Each...  .20  .03 

Wood  Curves,  Nos.  3,  4,  13,  19,  20  and  24.  Each..  .25  .05 

Wood  Curve,  No.  27  35  .08 


ADJUSTABLE  CURVE -RULER. 


2186.  Adjustable  Curve -Ruler,  14J  inches  long $1.87  $0.15 

2187.  Adjustable  Curve -Ruler,  30  inches  long 2.87  .35 

These  rulers  can  be  instantly  adjusted  and  retained  to 

any  form  of  curve. 

This  tool  is  recommended  by  architects  and  drafts- 
men, and  meets  a long-felt  want.  It  is  well  made,  neatly 
finished  and  nickel -plated. 

ELLIPSES,  HYPERBOLAS  AND  PARABOLAS. 


2190.  Hard  Rubber  Ellipses,  6 in  a set,  2 to  4j-inch. 

Per  set $1.50  $0.13 

2191.  Hard  Rubber  Ellipses,  10  in  a set,  1J  to  6-inch. 

Per  set 2.50  .16 

2194.  Wood  Ellipses,  6 in  a set,  2 to  4 J -inch.  Per  set...  1.25  .13 

2195.  Wood  Ellipses,  10  in  a set,  1J  to  6-inch.  Per  set..  2.00  .16 

2200.  Wood  Hyperbolas,  8 in  a set,  2 to  5J-inch.  Per 

set 1.50  .15 

2204.  Wood  Parabolas,  8 in  a set,  1J  to  5J-inch.  Per  set  1.50  .15 


W.  & L.  E.  GURLEY,  TROY,  N.  Y. 


359 


RAILROAD  CURVES. 


2210. 


No.  Price.  Post. 

Set  of  10  Curves,  cut  to  a scale  of  inches,  from  12 

to  120  inches  radius,  varying  every  12  inches. 

2210.  Rubber  Curves,  in  wood  box $7.00  $0.30 

2211.  Wood  Curves,  in  wood  box 4.50  .30 

Set  of  24  Curves,  cut  to  a scale  of  inches,  from  1 J 

to  24  inches  radius,  varying  every  J-inch  up  to  10 

inches  and  then  every  2 inches  up  to  24  inches. 

2214.  Rubber  Curves,  in  wood  box 17.00  .40 

2215.  Wood  Curves,  in  wood  box 10.00  .40 

Set  of  10  Curves,  cut  to  a scale  of  50  feet  to  the 

inch,  from  1°  to  10°,  varying  every  degree. 

2218.  Rubber  Curves,  in  wood  box 9.00  .30 

2219.  Wood  Curves,  in  wood  box 6.00  .30 

Set  of  20  Curves,  cut  to  a scale  of  50  feet  to  the 

inch,  from  1°  to  20°,  varying  every  degree. 

2222.  Rubber  Curves,  in  wood  box 18.00  .35 

2223.  Wood  Curves,  in  wood  box 12.00  .35 

Set  of  12  Curves,  cut  to  a scale  of  100  feet  to  the 

inch,  from  1°  to  12°,  varying  every  degree. 

2226.  Rubber  Curves,  in  wood  box 10.00  .30 

2227.  Wood  Curves,  in  wood  box 6.75  .30 

Set  of  24  Curves,  cut  to  a scale  of  100  feet  to  the 

inch,  from  30/  to  12°,  varying  every  30  minutes. 

2230.  Rubber  Curves,  in  wood  box 19.00,  .40 

2231.  \^ood  Curves,  in  wood  box 13.00  .40 

Set  of  20  Curves,  cut  to  a scale  of  200  feet  to  the 

inch,  from  1°  to  20°,  varying  every  degree. 

2234.  Rubber  Curves,  in  wood  box 15.00  .35 

2235.  Wood  Curves,  in  wood  box 10.00  .35 

Set  of  20  Curves,  cut  to  a scale  of  400  feet  to  the 

inch,  from  30/  to  10°,  varying  every  30  minutes. 

2238..  Rubber  Curves,  in  wood  box 14.00  .35 

2239.  Wood  Curves,  in  wood  box 9.50  .35 


360 


IV.  &•  L.  E.  GURLEY,  TROY,  N.  Y. 


PARALLEL  RULERS. 


2250. 


EBONY  PARALLEL  RULERS. 


No. 

Price. 

Post. 

No. 

Price. 

Post. 

2250. 

6 -inch. 

$0.30 

$0.04 

2253. 

15-inch.. 

$1.00 

$0.18 

2251. 

9-inch. 

50 

.06 

2254. 

18-inch.. 

1.25 

.20 

2252. 

12-inch. 

.08  | 

2255. 

24-inch.. 

2.00 

.24 

HARD  RUBBER  PARALLEL  RULERS. 

2260. 

6 -inch. 

$0.04 

2262. 

12-inch.. 

$1.25 

$0.16 

2261. 

9-inch. 

1.00 

.06 

2263. 

15-inch.. 

.18 

EBONY 

PARALLEL  RULERS,  ON 

ROLLERS. 

2270. 

9-inch. 

$2.75 

$0.20 

2272. 

15-inch.. 

$4.00 

$0.30 

2271. 

12-inch. 

3.25 

.25 

2273. 

18-inch.. 

5.00 

.35 

HARD 

RUBBER 

PARALLEL  RULERS,  ON 

ROLLERS. 

2275. 

9-inch. 

$3.50 

$0.20 

2277. 

15-inch.. 

$0.30 

2276. 

12-inch. 

4.25 

.25 

2278. 

18-inch.. 

6.00 

.35 

EBONY  PARALLEL  RULERS,  ON  ROLLERS. 

WITH  WHITE  EDGES,  DIVIDED  $,  \,  1 INCH  TO  THE  FOOT. 


2280.  12-inch. 

2281.  15-inch 


$7.50  $0.35 


W.  6-  Z.  E.  GURLEY,  TROY,  N.  Y 


361 


BRASS  PARALLEL  RULERS,  ON  ROLLERS. 


No. 

2285.  9-inch, 

2286.  12-inch, 


Price.  Post. 

17.25  $0.30 
8.50  .40 


No. 

2287.  15-inch, 

2288.  18-inch, 


Price.  Post. 

$10.00  $0.50 

12.00 


GERMAN  SILVER  PARALLEL  RULERS, 

ON  ROLLERS. 

2292.  9-inch.......  $8.50  $0.30  2294.  15-inch ..$12.00  $0.50 

2293.  12-inch 10.00  .40  2295.  18-inch 15.00 


PANTOGRAPHS  FOR  ENLARGING  OR 
REDUCING  DRAWINGS. 


2300. 


‘2300.  Pantograph,  hardwood,  brass  mountings,  with  arms 

21  inches  long $1.75  $0.25 

2302.  Pantograph,  hardwood,  nickel  - plated  mountings, 

with  arms  18  to  20  inches  long 2.50  .25 

2304.  Pantograph,  hardwood,  brass  mountings,  with  arms 

22  inches  long 3.50  .30 

2306.  Pantograph,  hardwood,  brass  mountings,  with  arms 

41  inches  long : 5.00  .50 


362  TV.  & L.  E.  GURLEY,  TROY,  N.  Y. 

DRAWING-PAPER. 


ARCHITECTS'  PAPER  FOR  PLANS. 

WHITE,  STRONG,  SMOOTH  SURFACE. 

No.  Price.  Post. 

2350.  Medium,  23xl8-incli,  per  sheet  6 cents  ; per  quire..  $1.25  $0.48 
2352.  Super  Royal,  28  x 20-inch,  per  sheet,  8 cents  ; per 

quire 1.75  .65 

2355.  30  inches  wide,  per  roll  of  10  yards 1.25  .40 

2356.  36  inches  wide,  per  roll  of  10  yards 1.50  .50 

2357.  42  inches  wide,  per  roll  of  10  yards 1.75  .60 

WHATMAN’S  DRAWING-PAPERS. 

SELECTED,  BEST  QUALITY,  GRAINED  SURFACE. 

2360.  Demy,  20 x 15-inch,  per  sheet,  5 cents  ; per  quire...  $0.95  $0.28 

2361.  Medium,  22  x 17-inch,  per  sheet,  7 cents  ; per  quire..  1.40  .36 

2362.  Royal,  24  x 19-inch,  per  sheet,  9 cents  ; per  quire...  1.80  .43 

2363.  Super  Royal,  27  x 19-inch,  per  sheet,  10  cents  ; per 

quire 2.10  .53 

2365.  Imperial,  30  x 22-inch,  per  sheet,  17  cents;  per 

quire 3.00  .66 

2368.  Double  Elephant,  40  x 26-inch,  per  sheet,  25  cents  ; 

per  quire 6.75  1.28 

WHATMAN’S  DRAWING-PAPER. 

MOUNTED  ON  MUSLIN. 

2370.  Royal,  24  x 19-inch,  per  sheet $0.38  $0.10 

2372.  Imperial,  30  x 22-inch,  per  sheet 45  .13 

2374.  Double  Elephant,  40x27-inch,  per  sheet 75  .18 

PATENT  OFFICE  DRAWING-PAPER. 

2380.  Patent  Office  Bristol -Board,  15  x 10-inch,  per  sheet, 

6 cents  ; per  dozen $0.60  $0.15 

2381.  Patent  Office  Bristol -Board,  20  x 15-inch,  per  sheet, 

12  cents  ; per  dozen 1.20  .30 

2385.  Patent  Office  Bristol-Board,  printed  with  border, 

etc.,  15  x 10-inch,  per  sheet,  10  cents  ; per  dozen  .85  .15 


W.  6-  Z.  E.  GURLEY,  TROY,  N.  K 


363 


DETAIL  DRAWING-PAPER,  CREAM  BUFF  TINT. 

SUPERIOR  QUALITY,  IN  ROLLS  OF  30  TO  40  LBS. 


No.  Price.  Post. 

2389.  30  inches  wide,  per  pound,  29  cents  ; per  yard $0.13  $0.10 

2390.  36  inches  wide,  per  pound,  29  cents  ; per  yard 15  .12 

2391.  42  inches  wide,  per  pound,  29  cents  ; per  yard 20  .20 


BLEACHED  MANILLA  PAPER. 

FOR  WORKSHOP  DRAWINGS,  BEST  AMERICAN  MAKE,  IN  ROLLS  OF  ABOUT 

50  POUNDS. 

2395.  36  inches  wide,  medium,  per  pound,  12  cents  ; per 

yard $0.08  $0.12 

2396.  42  inches  wide,  medium,  per  pound,  12  cents  j per 

yard 10  .14 

2397.  48  inches  wide,  medium,  per  pound,  12  cents  ; per 

yard 12 

2398.  54  inches  wide,  medium,  per  pound,  12  cents  ; per 

yard 15 


AMERICAN  WHITE  ROLL  DRAWING-PAPER. 


VERY  STRONG  AND  OF  EXCELLENT  QUALITY,  IN  ROLLS  OF 
ABOUT  40  POUNDS. 

2410.  36  inches  wide,  smooth  surface,  per  pound,  45 

cents;  per  yard $0.25  $0.12 

2411.  42  inches  wide,  smooth  surface,  per  pound,  45 

cents  ; per  yard 30  .14 

2413.  62  inches  wide,  smooth  surface,  per  pound,  45 

cents  ; per  yard 50 

2414.  72  inches  wide,  smooth  surface,  per  pound,  50 

cents  ; per  yard 65 

EXCELSIOR  WHITE  ROLL  DRAWING-PAPER. 

IN  ROLLS  OF  ABOUT  40  POUNDS. 

2420.  36  inches  wide,  grained  surface,  per  pound,  40 

cents;  per  yard $0.20  $0.12 

2421.  42  inches  wide,  grained  surface,  per  pound,  40 

cents;  per  yard 24  ,14 

Note.  — Small  quantities  of  paper  must  be  put  on  a wooden  roller 
when  sent  by  mail.  Several  yards  can  be  put  on  a single  roller,  with 
-but  little  extra  cost  for  postage.  The  pound  price  for  papers  Nos.  23$) 
to  2434  applies  only  to  full  rolls. 


364  IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 

BEST  EGGSHELL  DRAWING-PAPER. 

IN  ROLLS  OF  ABOUT  40  POUNDS. 

No.  Prick.  Post. 

2430.  36  inches  wide,  pebbled  surface,  per  pound,  50 

cents;  per  yard $0.33  $0.13 

2431.  42  inches  wide,  pebbled  surface,  per  pound,  50 

cents;  per  yard 38  .15 

2434.  58  inches  wide,  pebbled  surface,  per  pound,  50 

cents  ; per  yard 50 


MOUNTED  DRAWING-PAPER. 

WHITE,  MOUNTED  ON  MUSLIN,  IN  ROLLS  OF  10  YARDS. 

2450.  American,  36  inches  wide,  smooth  surface,  per  roll, 

$6.80;  per  yard $0.85  $0.25 

2451.  American,  42  inches  wide,  smooth  surface,  per  roll, 

$8.20;  per  yard 1.00  .30 

2453.  American,  62  inches  wide,  smooth  surface,  per  roll, 

$13.25;  per  yard 1.60 

2454.  American,  72  inches  wide,  smooth  surface,  per  roll, 

$18.00;  per  yard 2.30 

2460.  Eggshell,  36  inches  wide,  pebbled  surface,  per  roll, 

$7.50;  per  yard 1.00  .25 

2461.  Eggshell,  42  inches  wide,  pebbled  surface,  per  roll, 

$8.85;  per  yard 1.10  .30 

2463.  Eggshell,  58  inches  wide,  medium  thick,  pebbled 

surface,  per  roll,  $11.75  ; per  yard 1.40 

2464.  Eggshell,  58  inches  wide,  thick,  pebbled  surface, 

per  roll,  $13.00  ; per  yard 1.60 

Large  pieces  for  City,  County  or  State  Maps,  mounted  to  order. 

2467.  Paper  Cloth,  38  inches  wide,  smooth  surface,  per 

roll,  $4.50  ; per  yard 50  .20 

DRAWING-PARCHMENT. 

2468.  38  inches  wide,  medium,  per  roll  of  20  yards, 

$3.00;  per  yard $0.20  $0.12 

2469.  38  inches  wide,  thick,  per  roll  of  10  yards,  $3.20; 

per  yard 45  .1§ 


IV.  & L.  E.  CURLEY , TROY,  N.  Y.  365 

TRACING-PAPER. 

No.  Price.  Post. 

2470.  Pellucid,  common,  21  inches  wide,  per  yard,  5 

cents;  per  roll  of  20  yards $0.75  $0.18 

2472.  Vegetable,  30  inches  wide,  per  yard,  10  cents  ; per 

roll  of  20  yards 1.50  .40 

2474.  Bank  Note,  36  inches  wide,  per  yard,  10  cents  ; per 

roll  of  20  yards 1.62  .40 

2476.  Parchment,  40  inches  wide,  per  yard,  25  cents  ; per 

roll  of  20  yards 4.00  .60 

2478.  Bond,  42  inches  wide,  per  yard,  15  cents;  per  roll 

of  20  yards 2.25  .45 

2479.  Manilla,  common,  48  inches  wide,  per  yard,  7 

cents  ; per  roll  of  20  yards 1.00  .50 

2480.  Vegetable,  25  x 19  inches,  per  sheet,  10  cents ; per 

quire 2.00  .20 

2482.  Flaxine,  31x21  inches,  per  sheet,  12  cents;  per 

quire 2.50  .25 

2484.  Bond,  21  x 16  inches,  per  sheet,  6 cents  ; per  quire..  1.00  .20 

2486.  Bond,  30  x 19  inches,  per  sheet,  8 cents  ; per  quire..  1.40  .30 

2493.  Pounce  Powder,  in  tin  shaker,  for  Tracing-Paper  or 

Tracing-Cloth,  each 15  .07 

IMPERIAL  TRACING-CLOTH. 

IN  ROLLS  OF  24  YARDS,  FACE  GLAZED  AND  BACK  DULL. 

2495.  30  inches  wide,  per  yard,  35  cents;  per  roll $6.90  $0.70 

2496.  36  inches  wide,  per  yard,  40  cents;  per  roll 7.60  1.10 

2497.  42  inches  wide,  per  yard,  55  cents  ; per  roll 10.50  1.25 

2498.  48  inches  wide,  per  yard,  70  cents  ; per  roll 14.20 

2499.  54  inches  wide,  per  yard,  75  cents  ; per  roll 15.00 

PREPARED  BLUE-PRINT  PAPERS. 

BEST  QUALITY  ; READY  FOR  IMMEDIATE  USE. 

2506.  Sensitized  Paper,  24  inches  wide,  per  yard,  15 

cents;  per  roll  of  10  yards $1.20  $0.35 

2508.  Sensitized  Paper,  30  inches  wide,  per  yard,  18 

cents;  per  roll  of  10  yards 1.50  .45 

2510.  Sensitized  Paper,  36  inches  wide,  per  yard,  20 

cents;  per  roll  of  10  yards .i 1.65  .65 

2512.  Sensitized  Paper,  42  inches  wide,  per  yard,  22 

cents  ; per  roll  of  10  yards 1.80  .65 

2515.  White  Ink,  for  altering  Blue- Prints,  per  bottle 20  .06 

2516,  Red  Ink,  for  altering  Blue-Prints,  per  bottle 20  .06 


366 


IV.  &•  L.  E.  GURLEY,  TROY,  N.  Y. 


BLUE -PRINT  PAPER,  NOT  PREPARED. 


No.  Price.  Post. 

2520.  24  inches  wide,  per  roll  of  10  yards $0.80  $0.35 

2522.  30  inches  wide,  per  roll  of  10  yards 1.00  .45 

2524.  36  inches  wide,  per  roll  of  10  yards 1.15  .55 

2526.  24  inches  wide,  per  roll  of  50  yards 3.20 

2528.  30  inches  wide,  per  roll  of  50  yards 4.00 

2530.  36  inches  wide,  per  roll  of  50  yards 4.75 

• 


PRINT-FRAMES  AND  BATH -TRAYS. 


W.  <5-  Z.  E.  GURLEY,  TROY,  N.  Y. 


367 


PRINT-FRAMES  AND  BATH-TRAYS. 

No.  Price. 

2534.  Print-Frame,  complete  with  Plate-Glass  and  Cush- 
ion, 24  x 20  inches,  clear  exposure $10.00 

2536.  Print-Frame,  complete  with  Plate-Glass  and  Cush- 
ion, 30x34  inches,  clear  exposure 12.00 

2538.  Print-Frame,  complete  with  Plate-Glass  and  Cush- 
ion, 42  x 30  inches,  clear  exposure. 22.00 

2540.  Zinc  Bath-Tray,  for  washing  copies,  24x20  inches..  3.75 

2542.  Zinc  Bath-Tray,  for  washing  copies,  30  x 24  inches..  4.50 

2544.  Zinc  Bath-Tray,  for  washing  copies,  42  x 30  inches..  6.00 

(See  cut  on  page  366.) 


THE  BLUE  PROCESS  OF  COPYING  TRACINGS. 

Special  attention  is  directed  to  this  easy  process  of  copying  tracings, 
and  its  great  value  to  all  Engineers,  Architects  and  Mechanical  Draftsmen 
is  fully  recognized. 

If  not  convenient  to  procure  a Print -Frame,  blue-prints  can  be  made 
readily  by  following  these  directions  : — 

1.  Provide  a flat  board  as  large  as  the  tracing  which  is  to  be  copied. 

2.  Lay  on  this  board  a cushion  of  blanket  or  felt  about  J-inch  thick, 
to  give  a slightly  yielding  backing  for  the  paper. 

3.  Lay  on  the  blanket  the  prepared  paper  with  the  sensitive  side 
uppermost. 

4.  Lay  on  this  paper  the  tracing,  smoothing  it  out  as  perfectly  as  pos- 
sible, so  as  to  insure  a perfect  contact  with  the  paper. 

5.  Lay  on  the  tracing  a plate  of  clear  glass,  which  should  be  heavy 
enough  to  press  the  tracing  close  down  upon  the  paper.  Ordinary  plate- 
glass,  one  quarter  of  an  inch  in  thickness,  is  sufficient. 

6.  Expose  the  whole  to  a clear  sunlight  by  pushing  it  out  on  a shelf 
from  a window,  or  in  any  other  convenient  way,  from  four  to  six  minutes 
[in  winter,  six  to  ten  minutes].  If  a clear  sky  only  can  be  had,  the 
exposure  must  be  continued  from  twenty  to  thirty  minutes  ; and  under  a 
cloudy  sky  from  sixty  to  ninety  minutes  may  be  needed,  the  shade  depend- 
ing on  the  time. 

7.  'Remove  the  prepared  paper  and  wash  it  freely  for  one  or  two 
minutes  in  clear  water,  and  hang  it  by  one  corner  to  dry. 

Note. — Too  light  a blue  means  under-exposure,  and  too  dark  a blue  is  over- 
exposure. 


368  IV.  &>  L.  E.  GURLEY,  TROY,  N.  Y. 

TIN  TUBES  WITH  SCREW  TOPS. 

FOR  HOLDING  PREPARED  PAPER,  TRACINGS,  DRAWINGS,  ETC. 


No.  Price.  Post. 

2546.  Plain  Tin  Tube,  screw  top,  24  x 2J  inches $1.00  $0.30 

2547.  Plain  Tin  Tube,  screw  top,  30  x 2J  inches 1.15  .35 

2548.  Plain  Tin  Tube,  screw  top,  36  x 2^  inches 1.25  .40 

2549.  Plain  Tin  Tube,  screw  top,  42  x 2J  inches 1.35  .45 


TOWNSHIP  PLOTTING-PAPER. 

2550.  Township  Plotting- Paper,  Rulings  6x6  inches, 

blocks  1 inch  square,  per  quire... $0.60  $0.10 

2552.  Township  Plotting- Paper,  Rulings  12  x 12  inches, 

blocks  2 inches  square,  per  quire 85  .25 

2553.  Township  Plotting- Paper,  Rulings  18  x 15  inches, 

per  quire 3.00  .30 


CROSS-SECTION  SKETCH-BLOCKS. 

24  SHEETS. 

2554.  Sketch-Block,  7x5  inches,  24  sheets,  ruled  of  an 

inch $0.75  $0.06 

2555.  Sketch-Block,  10  x 7 inches,  24  sheets,  ruled  -fa  of 

an  inch / 1.25  .12 

2557.  Sketch-Block,  18  x 13  cm.,  metric  ruling 75  .06 

2558.  Sketch-Block,  26  x 18  cm.,  metric  ruling 1.25  .12 


PLAIN  SKETCH-BLOCKS. 

EACH  BLOCK  CONSISTS  OF  32  SHEETS  OF  BEST  QUALITY  WHATMAN’S 

DRAWING-PAPER. 


2560.  Sketch-Block,  7 x 5 inches,  unbound $0.50  $0.08 

2561.  Sketch-Block,  10  x 7 inches,  unbound 90  .16 

2563.  Sketch-Block,  14  x 10  inches,  unbound 1.60  .40 

2565.  Sketch- Block,  20  x 14  inches,  unbound 3.00  .70 

2570.  Sketch-Block,  7 x 5 inches,  bound 1.00  .12 

2571.  Sketch-Block,  10  x 7 inches,  bound 1.50  .32 

2573.  Sketch-Block,  14  x 10  inches,  bound 2.40  .56 

2575.  Sketch-Block,  20x14  inches,  bound 4.50 


The  unbound  blocks  have  a stiff  pasteboard  backing. 

The  bound  blocks  have  cloth  sides  and  leather  back,  with  a portfolio 
and  loop  for  pencil  inside.  The  portfolio  will  last  for  a number  of  blocks. 


W.  6°  Z.  E.  GURLEY,  TROY \ N.  Y 


369 


PROFILE -PAPERS. 

(Prices  on  page  370.) 


Profile-Paper,  Plate  B. 


Profile-Paper,  Metric 


370  W.  & L.  E.  GURLEY,  TROY,  N.  Y. 

PROFILE-PAPER. 

Sheets  : Lines  printed  in  green. 

Continuous  : Lines  printed  in  green  or  red. 

Continuous  on  tracing-paper  : Lines  printed  in  orange. 

Plate  A.  Rulings  4 x 20  to  the  inch. 

No.  Price.  Post. 

2580.  Plate  A,  sheet  42  x 15  inches,  per  quire $8.50  $0.75 

2581.  Plate  A,  sheet  42  x 15  inches,  per  sheet 40  .05 

2584.  Plate  A,  continuous,  20  inches  wide,  50  yards  in 

roll,  per  yard 24  .05 

2586.  Plate  A,  continuous,  20  inches  wide,  mounted  on 

muslin,  20  yards  in  roll,  per  yard 65  .08 

2588.  Plate  A,  continuous,  20  inches  wide,  on  tracing- 

paper,  50  yards  in  roll,  per  yard 24  .05 

Plate  B.  Rulings  4 x 30  to  the  inch. 

2595.  Plate  B,  sheet  42  x 13  J inches,  per  quire 8.50  .75 

2596.  Plate  B,  sheet  42  x 13  J inches,  per  sheet 40  .05 

2600.  Plate  B,  continuous,  20  inches  wide,  50  yards  in 

roll,  per  yard.  -. .24  .05 

2602.  Plate  B,  continuous,  20  inches  wide,  mounted  on 

muslin,  20  yards  in  roll,  per  yard 65  .08 

2604.  Plate  B,  continuous,  20  inches  wide,  on  tracing- 

paper,  50  yards  in  roll,  per  yard 24  .05 

2610.  Metric. — In  continuous  roll,  rulings  50  centimeters 
wide,  in  millimeters,  with  each  fifth  millimeter, 
each  centimeter,  and  each  decimeter,  proportion- 
ally heavier  than  the  millimeters,  50  yards  in  roll, 

per  yard 24  .05 

2612.  Metric,  continuous,  mounted  on  muslin,  20  yards  in 

roll,  per  yard ;65  .08 

CROSS-SECTION  PAPERS. 

Sheets  : Lines  printed  in  green. 

Continuous  : Lines  printed  in  green. 

2620.  Cross-Section  Paper,  Plate  C,  rulings  20  x 16  inches, 

8 feet  to  inch,  per  sheet,  20  cents  ; per  quire $3.50  $0.40 

2621.  Cross-Section  Paper,  Plate  F,  rulings  20  x 16  inches, 

10  feet  to  inch,  per  sheet,  20  cents  ; per  quire 3.50  .40 

2622.  Continuous  Cross-Section  Paper,  Plate  F,  20  inches 

wide,  in  rolls  of  50  yards,  per  yard  ............ 24  .05 


W.  & L.  E.  GURLEY,  TROY,  N.  Y.  371 


Plate  F.  10  feet  to  one  inch. 

No.  Price.  Post. 

2623.  Continuous  Cross-Section  Paper,  Plate  F,  20  inches 
wide,  ruled  10  feet  to  inch  on  tracing-paper,  in 
rolls  of  50  yards,  per  yard $0.24  $0.05 


Plate  G. 

2624.  Cross-Section  Paper,  Plate  G,  rulings  20  x 16  inches, 

10  feet  to  inch,  every  fifth  line  heavy,  per  sheet, 

20  cents  ; per  quire 3.50  .40 

2625.  Cross-Section,  Plate  G,  printed  on  Parchment  Trac- 

ing-Paper, in  sheets,  20x16  inches,  per  sheet, 

20  cents  ; per  quire - 3.50  .25 

2626.  Cross-Section  Paper,  Plate  H,  rulings,  20  x 16 

inches,  16  feet  to  inch,  per  sheet,  20  cents ; per 

quire 3.50  .40 

2627.  Continuous  Cross-Section  Paper,  Plate  H,  20  inches 

wide,  in  rolls  of  50  yards,  per  yard 24  .05 

2630.  Cross-Section  Paper,  Metric,  rulings  every  millimeter, 
size  of  sheet,  50  x 40  centimeters,  per  sheet,  20 
cents;  per  quire 3.50  .40 


872 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 


Millimeter. 


No.  Price.  Post. 

2631.  Continuous  Cross-Section  Paper,  Metric,  rulings  every 
millimeter,  50  centimeters  wide,  in  rolls  of  50  yards, 
per  yard $0.24  $0.05 


The  following  list  of  Cross-Section  Papers,  being  ruled, 
are  much  cheaper  than  those  printed  from  copper  plates  : 


2635.  Ruled  Cross-Section  Paper,  4 spaces  to  inch,  21  x 16 

inches,  per  quire  1.00  .35 

2636.  Ruled  Cross-Section  Paper,  8 spaces  to  inch,  21  x 16 

inches,  per  quire  1.00  .35 

2637.  Ruled  Cross-Section  Paper,  10  spaces  to  inch, 

21  x 16  inches,  per  quire 1.00  .35 

2638.  Ruled  Cross-Section  Paper,  12  spaces  to  inch, 

21x16  inches,  per  quire 1.00  .35 

WRITING-PAPER,  ENVELOPES,  ETC. 

2660.  Commercial  Note-Paper,  8x5  inches,  fine,  per 

ream,  $2.00;  per  quire $0.15  $0.08 

2662.  Letter-Paper,  10  x 8 inches,  fine,  per  ream,  $3.50; 

per  quire 20  .12 

2664.  Foolscap  Paper,  12J  x 8 inches,  fine,  per  ream, 

$4.50;  per  quire .30  .15 

2665.  Specification  Paper,  12J  x 8 inches,  fine,  per  ream, 

$5.00;  per  quire 35  .15 

2668.  Type-Writer  Paper,  10J  x 8 inches,  fine,  per  ream, 

$1.50;  per  quire 12  .05 

2670.  Envelopes,  white,  5J  x 3f  inches,  fine,  per  hun- 
dred  30  .15 

2672.  Envelopes,  white,  8|-  x 3|-  inches,  fine,  per  hun- 
dred  75  .20 

2674.  Letter- Press  Copying-Books,  500  pages.  12  x 10  in- 
ches  .' 1.75  .28 


W.  & L,  E.  GURLEY,  TROY,  N.  Y.  373 

No.  Price.  Post. 

2675.  Stafford’s  Black  Writing  and  Copying-Ink,  quart 

bottle $1.00 

2676.  Arnold’s  Blue-Black  Copying-Ink,  quart  bottle 1.00 

2678.  David’s  Carmine  Ink,  2 oz.  bottle 36  $0.08 

2679.  Letter  Copying- Press,  No.  5,  15x10  inches,  iron 

body,  wheel  handle 7.50 


THUMB-TACKS  AND  HORN  CENTERS. 


2680  TO  2690.  2708. 


2680  TO  2690.  2708. 

2680.  Brass  Thumb-Tacks,  round  head,  f-inch  diam.,  per 

doz $0.10  $0.02 

2681.  Brass  Thumb-Tacks,  round  head,  f-inch  diam.,  per 

doz 20  .02 

2682.  Brass  Thumb-Tacks,  round  head,  f-inch  diam.,  per 

doz 30  .02 

2684.  German  Silver  Thumb-Tacks,  round  head,  f-inch 

diam.,  per  doz 28  .02 

2685.  German  Silver  Thumb-Tacks,  round  head,  f-inch 

diam.,  per  doz 35  .02 

2686.  German  Silver  Thumb-Tacks,  round  head,  f-inch 

diam.,  per  doz 55  .03 

2689.  German  Silver  Thumb-Tacks,  round  head,  superior, 

f-inch  diam.,  per  doz * 70  .02 

2690.  German  Silver  Thumb-Tacks,  round  head,  superior, 

f-inch  diam.,  per  doz 90  .03 

2692.  Steel  Thumb-Tacks,  common,  f-inch  diam.,  per 

doz 08  .02 

2694.  Steel  Thumb-Tacks,  common,  T9g-inch  diam.,  per 

doz 12  .02 

2697.  Steel  Thumb-Tacks,  superior,  T5^-inch  diam. , per  doz.  .80  .02 

2700.  Thumb-Tack  Lifter  and  Paper-Knife 20  .02 

2703.  Brass  Paper-Fasteners,  prongs  f-inch,  per  doz 08  .02 

2705.  Brass  Paper-Fasteners,  prongs  f-inch,  in  box,  per 

hundred 50  .08 

2707.  Horn  Center,  plain 10  .01 

2708.  Horn  Center  with  German  silver  rim 50  .01 

2710.  Handy  Paper-Cutter,  brass  mounted,  for  cutting 

drawings  from  the  board 35  .03 


374  W.  L.  E.  GURLEY,  TROY,  N.  Y. 

CONTINUOUS  PROFILE-BOOKS. 


2715. 


These  books  are  for  field  or  office  purposes,  being  printed  on  a tough 
thick  paper,  and  mounted  upon  a continuous  piece  of  muslin  and  bound  in 
book  form  with  flexible  morocco  covers,  convenient  for  the  pocket.  Each 
page  will  contain  a profile  of  three  thousand  feet  in  length,  so  that  each 
folio  will  contain  an  average  section  of  a road  as  usually  laid  out  for  con- 
struction. Railroad  and  other  engineers  will  find  them  very  useful.  The 
rulings  correspond  to  our  large  profile-plates  A and  B. 


No.  Price.  Post. 

2715.  Plate  A,  about  8Jx  6 inches,  profile  12  miles $2.00  $0.15 

2716.  Plate  A,  about  8 J x 6 inches,  profile  25  miles 3.25  .18 

2717.  Plate  A,  about  8J  x 6 inches,  profile  50  miles 5.25  .20 

2718.  Plate  A,  about  8 J x 6 inches,  profile  100  miles 9.50  .28 

2720.  Plate  B,  about  8 x 5 J-  inches,  profile  12  miles 2.00  .13 

2721.  Plate  B,  about  8 x 5 \ inches,  profile  25  miles 3.25  .15 

2722.  Plate  B,  about  8 x 5J  inches,  profile  50  miles 5.25  .18 


2723.  Plate  B,  about  8 x 5J  inches,  profile  100  miles  9.50  .25 

PLAT  AND  PROFILE  BOOKS. 

These  Books  are  9J  x 4J  inches,  oblong,  with  flexible  morocco  covers, 
containing  36  profile  pages,  plate  B,  and  the  opposite  pages  are  blank 
for  plats,  etc. 

2724.  Dunham’s  Plat  and  Profile  Book $1.00  $0.08 


IV.  &>  L.  E.  GURLEY, \ TROY,  N.  Y.  375 

ENGINEERS’  BLANK  FIELD-BOOKS. 

LEATHER  BINDING  AND  ROUNDED  CORNERS. 


No.  Price.  Post. 

2725.  Level-Books,  6f  x 4J  inches,  60  leaves,  per  dozen, 

$5.00;  or  single $0.50  $0.05. 


2728.  Transit- Books,  6f  x 4J  inches,  60  leaves,  per  dozen, 

$5.00;  or  single 50  .05 


2731.  Record-Books,  6§  x 4J  inches,  60  leaves,  per  dozen, 
$5.00  ; or  single 


.50 


.05 


376 


W.  <5r=  L.  E.  GURLEY,  TROY,  N.  Y 


BLANK  FIELD-BOOKS. — Continued. 

No.  Prick.  Post. 

2736.  Cross-Section  Books,  6f  x 4J-  inches,  60  leaves,  ruled 

5 spaces  per  inch,  per  dozen  $5.00  ; or  single $0.50  $0.05 

2738.  Cross-Section  Books,  6f  x 4J  inches,  60  leaves,  ruled 

10  spaces  per  inch,  per  dozen,  $5.00  ; or  single...  .50  .05 

2740.  Cross-Section  Books,  8x7  inches,  80  leaves,  ruled 

5 spaces  per  inch,  per  dozen,  $10.00  ; or  single...  1.00  .15 

2742.  Cross-Section  Books,  8x7  inches,  80  leaves,  ruled 

10  spaces  per  inch,  per  dozen,  $10.00  ; or  single..  1.00  .15 


LYONS’  TABLES. 

2746.  Lyons’  Tables.  A set  of  tables  for  finding  at  a glance  the  true 
cubical  contents  of  Excavation  and  Embankment  for  the 
following  Bases,  and  Ground  and  Side  Slopes.  By  E.  M. 


Lyons,  C.  E. 

Sheet  No.  5.  Base  15  feet,  Slopes J to  1 

Sheet  No.  17.  Base  25  feet,  Slopes 1J  to  1 

Sheet  No.  18.  Base  26  feet,  Slopes . 1 J to  1 

Sheet  No.  19.  Base  28  feet,  Slopes J to  1 

Sheet  No.  20.  Base  30  feet,  Slopes 1 to  1 

Sheet  No.  21.  Base  30  feet,  Slopes 1J  to  1 

Sheet  No.  22.  Base  30  feet,  Slopes 1J  to  1 

Sheet  No.  23.  Base  32  feet,  Slopes 1 to  1 

Sheet  No.  24.  Base  32  feet,  Slopes 1J  to  1 

Per  sheet 15  cents  ; post,  5 cents. 


The  Tables  are  printed  in  clear,  bold  type,  on  tinted  paper,  sheets 
25  x 16  inches.  They  may  be  used  by  candle-light  without  injuring  the 
eyesight.  Each  sheet  is  complete  in  itself,  and  embraces  all  that  is 
wanted  in  connection  with  Base  or  Slope  designated,  whether  on  level  or 
side-hill  cross-section. 

Tables  Nos.  1,  2,  3,  4,  6,  7,  8,  9,  10,  11,  12,  13,  14,  15  and  16, 
quoted  in  our  previous  catalogues,  are  now  out  of  print. 


tV.  & L.  E.  GURLEY,  TROY,  N.  Y.  377 

LEAD-PENCILS.  (Black  Leads.) 

No.  Price.  Post. 

2750.  Faber’s  Hexagon,  Siberian,  best  Drawing,  Nos.  2 B 

to  8 H,  per  dozen $1.25  $0.12 

2752.  Faber’s  Hexagon,  Drawing,  Nos.  1 to  5,  per  dozen..  .75  .04 

2754.  Faber’s  Round,  Drawing,  Nos.  1 to  4,  per  dozen 60  .04 

2756.  Faber’s  Round,  No.  4,  small,  for  Drawing-Com- 
passes, per  dozen 60  .02 

2758.  Faber’s  Round,  Nos.  2 and  8,  with  rubber  tip,  for 

offices,  per  dozen 50  .04 

2765.  Faber’s  Artists’  Pencil,  with  movable  lead,  H to 

6 H,  each 25  .02 

2768.  Faber’s  Siberian  Leads,  H to  6 H,  for  Artists’  Pen- 
cil, 6 in  box,  per  box . .50  .04 

These  leads  fit  the  pencil  legs  of  modern  Draw- 
ing-Compasses. 

2770.  Faber’s  Siberian  Round  Pencils,  5 in  box,  2 B to 

H,  per  box 50  .04 

2771.  Faber’s  Siberian  Round  Pencils,  7 in  box,  3 B to 

2 H,  per  box 65  .05 

2772.  Faber’s  Siberian  Round  Pencils,  10  in  box,  4 B to 

4 H,  per  box 90  .08 

2774.  Faber’s  Siberian  Round  Pencils,  5 in  box,  with 

knife  and  rubber,  per  box 75  .05 

2778.  Hardtmuth’s  Koh-i-noor  Pencils,  Hexagon,  Super- 
fine, H to  8 H,  per  dozen 1.25  .12 

COLORED  PENCILS  AND  CRAYONS. 

2785.  Faber’s  Round,  Red,  Blue,  Green  and  Yellow  Pen- 
cils, per  dozen $0.75  $0.05 

2790.  Faber’s  Round,  Wax  Crayon  Pencils,  6 in  box, 

assorted  colors,  per  box 75  .05 

2791.  Faber’s  Round,  Wax  Crayon  Pencils,  12  in  box, 

assorted  colors,  per  box 1.40  .15 

2793.  Faber’s  Flat  Red  Chalk  Pencils,  for  marking  stakes, 

per  dozen 50  .05 


2795. 

(See  page  378.) 


378  W.  &■  L.  E.  GURLEY,  TROY,  N.  Y. 

No.  Price.  Post. 

2795.  Venetian  Crayons,  dark  red,  for  marking  stakes, 

per  dozen $0.60  $0.15 

2796.  Venetian  Crayons,  dark  blue,  for  njarking  stakes, 

per  dozen 60  .15 

2797.  Hexagon  Lumber  Crayons,  red,  blue  or  black,  per 

dozen 75  .15 

These  crayons  are  superior  quality  and  do  not  soil 
the  hands. 

STEEL  LETTERING  AND  WRITING-PENS. 

2800.  Gillott’s  Mapping-Pens,  per  dozen $0.60  $0.02 

2801.  Gillott’s  Lithographic  Pens,  per  dozen 60  .02 

2802.  Gillott’s  Crow  Quill  Pens,  per  dozen 60  .02 

2806.  Gillott’s  Writing- Pens,  No.  170,  per  dozen,  10 

cents;  per  gross 1.05  .10 

2807.  Gillott’s  Writing-Pens,  No.  308,  per  dozen,  15 

cents;  per  gross 1.40  .10 

2810.  Falcon  Writing-Pens,  No.  048,  per  dozen,  10  cents  ; 

per  gross 75  .04 

2812.  Spencerian  Writing-Pens,  per  dozen,  15  cents ; per 

gross 1.25  .10 

2814.  Commercial  Writing-Pens,  per  dozen,  10  cents  ; per 

gross 75  .04 

2816.  Penholders,  black  handle,  nickel  tip,  for  office  use, 

per  dozen 50  .05 

ROUND-WRITING  PENS,  FOR  ORNAMENTAL 

LETTERING. 

ggisi 

^svri'''"  if  ^Essaiiaaiii 

2820.  2824. 

2820.  Pens,  single  pointed,  Nos.  1 to  6,  assorted,  per 

dozen $0.12  $0.02 

2822.  Pens,  single  pointed,  Nos.  1 to  6,  assorted,  per  gross,  1.00  .15 

2824.  Pens,  double  pointed,  Nos.  10,  20  and  30,  assorted, 

per  dozen 35  .03 

2826.  Sample  assortment  of  25  Pens,  per  box 35  .04 

2828.  Penholders  for  round- writing  pens,  each 10  .02 

2830.  Text-Book  to  round- writing  with  full  instructions 65  .05 

2831.  Copy-Book  for  round- writing  practice... 35  .05 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 


379 


STEEL  ERASING-KNIVES  AND  PENCIL- 


SHARPENERS. 

No.  Price.  Post. 

2835.  Steel  Blade  Eraser,  Cocoa  handle $0.35  $0.03 

2836.  Steel  Blade  Eraser,  Ivory  handle 50  .03 

2838.  Steel  Eraser,  long  knife-blade,  Cocoa  handle 50  .03 


2840. 


2840.  Faber’s  New  Pencil-Sharpener  (superior) 25  .03 

2842.  Common  Pencil-Sharpener 10  .02 

2843.  Fine  Steel  Pencil-File,  with  sheath 25  .03 

2844.  Fine  Steel  Pencil-File,  with  Tack-lifter  at  end 25  .03 


ERASING  RUBBER. 


2850.  2862.  2866. 


2850.  2862.  2866. 

2850.  Faber’s  Artists’  Rubber,  If  xl  inch,  each $0.05  $0.01 

2852.  Faber’s  Artists’  Rubber,  If  x If  inches,  each 10  .02 

2854.  Faber’s  Artists’  Rubber,  2 x If  inches,  each 15  o03 

2856.  Faber’s  Artists’  Rubber,  2f  x 1J  inches,  each. ,25  ,03 


380 


W.  & L.  E.  GURLEY,  TROY,  N.  Y 


No. 

2860. 

2862. 

2864. 

2866. 

2867. 

2868. 


Price.  Post. 


Faber’s  Artists’  Rubber,  black,  pure  gum,  2 x If 

inches,  each $0.20  $0.03 

Faber’s  Ink-Eraser,  If  x 1 inch,  each 05  .01 

Faber’s  Ink-Eraser,  2f  x If  inches,  each 20  .03 

Faber’s  Combined  Ink  and  Pencil-Eraser,  2J  x 1 

inch,  each 15  «02 

Faber’s  Combined  Ink  and  Pencil-Eraser,  2f  x If 

inches,  each 25  .03 

Faber’s  Typewriters’  Rubber,  3J  x f inch,  each 10  .02 


2870. 


2870.  Faber’s  Pointed  Rubber,  2f  x TB¥  inch,  each 09  .01 

2871.  Faber’s  Pointed  Rubber,  3 x f inch,  each 12  .01 


2872. 


2872.  Velvet  Rubber,  oblong,  If  x f inch,  each 05  .01 

2874.  Velvet  Rubber,  oblong,  2f  x X inch,  each 10  .02 

2876.  Velvet  Rubber,  oblong,  3f  x f inch,  each 20  .03 

2878.  Velvet  Rubber,  flat,  3 x 2f  x T9^-  inch,  each 50  .06 


2880. 


2880.  Bevel  Rubber,  oblong,  2§  x § inch,  each 05  .01 

2882.  Bevel  Rubber,  oblong,  3 x | inch,  each 10  .02 

2884.  Bevel  Rubber,  oblong,  3f  x f inch,  each 15  .03 

2886.  Bevel  Rubber,  oblong,  3f  x f inch,  each .25  .04 


W.  & L.  E.  GURLEY,  TROY,  N.  K 


381 


No. 

2887. 

2888. 
2889. 


2890. 

2891. 

2892. 

2893. 


2895. 

2896. 
2898. 


2900. 

2902. 

2904. 

2905. 
2907. 


Hardtmuth’s  Pliable  Rubber,  grey,  flat,  No.  30. 
Hardtmuth’s  Pliable  Rubber,  grey,  flat,  No.  20. 
Hardtmuth’s  Pliable  Rubber,  grey,  flat,  No.  12 


2890. 

Multiplex  Rubber,  superior  quality,  2 x J inch,  each.. 
Multiplex  Rubber,  superior  quality,  2J  x f inch,  each 
Multiplex  Rubber,  superior  quality,  2J  x f inch,  each 
Multiplex  Rubber,  superior  quality,  2f  x 1 J inches, 
each 


Price. 

$0.10 

.15 

.25 


0.10 

.15 

.25 

.37 


2896. 

Sponge  Rubber,  for  cleaning  drawings,  2 J x If  x f 


inch .30 

Sponge  Rubber,  for  cleaning  drawings,  2x2x1 

inch 30 

Sponge  Rubber,  • for  cleaning  drawings,  4x2x1 

inch .60 

RUBBER  BANDS. 

Rubber  Bands,  No.  8,  -J  x y1^  inch,  per  gross $0.15 

Rubber  Bands,  No.  29,  1J  x ^ inch,  per  gross 65 

Rubber  Bands,  No.  61,  2 x | inch,  per  gross 1.00 

Rubber  Bands,  No.  63,  3 x J-  inch,  per  gross 1.50 

Rubber  Bands,  No.  200,  11  sizes  assorted,  1J  to  3 

inches,  per  box 1.00 


Post. 

$0.02 

.03 

.04 


0.02 

.02 

.03 

.04 


.03 

.03 

.06 


$0.02 

.05 

.15 

.20 

.18 


382 


IV.  &*  L.  E.  GURLEY,  TROY,  N.  Y. 


HIGGINS’  DRAWING-BOARD  AND  LIBRARY 


MUCILAGE. 

No.  Price.  Post. 

2915.  Drawing-Board  Mucilage,  fine  quality,  3-ounce  jar..  $0.15  $0.13 

2916.  Drawing-Board  Mucilage,  fine  quality,  6-ounce  jar..  .25  .20 

2917.  Drawing-Board  Mucilage,  fine  quality,  14-ounce  jar  .50  .30 

2918.  Taurine  Mucilage,  fine  quality,  2-ounce  bottle  with 

brush  .10  ,10 

2919.  Taurine  Mucilage,  fine  quality,  4-ounce  bottle  with 

brush 20  .15 

2920.  Taurine  Mucilage,  fine  quality,  pin!  bottle  without 

brush 50  .30 

2921.  Taurine  Mucilage,  fine  quality,  quart  bottle  without 

brush 80 

2923.  Photo-Mounter,  fine  quality,  3-ounce  jar 15  .13 

2924.  Photo-Mounter,  fine  quality,  6-ounce  jar 25  .20 


2915. 


2925. 


W.  & L . E.  GURLEY,  TROY,  N.  Y 


383 


HIGGINS'  AMERICAN  LIQUID  DRAWING-INKS. 


No.  Price. 

2925.  Waterproof  Black  Ink,  small  bottle $0.25 

2926.  Waterproof  Black  Ink,  8-oz.  bottle 2.00 

2928.  General  Black  Ink  (not  waterproof),  small  bottle 25 

2929.  General  Black  Ink  (not  waterproof),  8-oz.  bottle 2.00 


No.  Price. 

2930.  Waterproof  Carmine. ..$0.25 

2931.  Waterproof  Scarlet 25 

2932.  Waterproof  Vermilion  .25 

2933.  Waterproof  Blue 25 

2934.  Waterproof  Indigo 25 

2942.  Waterproof  Ink,  any  of  the 

bottle 


No.  Price. 

2935.  Waterproof  Violet $0.25 

2936.  Waterproof  Green 25 

2937.  Waterproof  Yellow  ...  .25 

2938.  Waterproof  Brown 25 

2939.  Waterproof  Orange  ...  .25 

above  colors,  per  large  ( 8-oz. ) 

> 2.00 


Postage  on  the  above  inks,  7 cents  each  small  bottle,  and  30  cents 
each  8-oz.  bottle. 


WINSOR  & NEWTON’S  WATER-COLOR  LIQUIDS. 

IN  GLASS  BOTTLES. 


No. 

Price. 

No. 

Price. 

2945. 

Indian  Ink,  Black... 

$0.30 

2950. 

Silver  Ink 

$0.30 

2946. 

Chinese  White 

.30 

2951. 

Gold  Ink 

.30 

2947. 

Carmine 

.30 

2952. 

Indelible  Brown 

.30 

2948. 

Sepia 

.30 

2953. 

Prout’s  Brown 

.30 

2949. 

Prussian  Blue 

.30 

2954. 

Extract  of  Ox  Gall... 

.30 

Postage  on  the  above  inks,  6 cents  each  bottle. 


MISCELLANEOUS  LIQUID  DRAWING-INKS. 


No.  Price.  Post. 

2956.  Bourgeois  Black  India  Ink,  per  bottle $0.25  $0.06 

2957.  Photo-Drawing  Ink,  Dead  Black,  per  bottle 20  .06 

2958.  Box  of  Indelible  Drawing-Inks,  six  bottles  (Blue, 

Brown,  Carmine,  Green,  Scarlet,  Yellow),  per 

box 1.50  .35 

2959.  Winsor  & Newton’s  Waterproof  Drawing-Inks 

(Black,  Brown,  Carmine,  Emerald  Green,  In- 
digo, Vermilion,  Yellow),  per  bottle .25  .06 


384 


W.  & L.  E.  GURLEY,  TROY,  N.  Y. 


CHINESE  INDIA  INK  FOR  GENERAL  DRAWING. 


2968. 


No.  Price.  Post. 

2960.  Oval,  Black,  Lion  Head,  3 J inches,  per  cake $0.35  $0.02 

2962.  Round,  Black,  Lion  Head,  2J  inches,  per  cake 25  .02 

2963.  Round,  Black,  Lion  Head,  4J  inches,  per  cake 65  .04 


2965.  Hexagon,  Black,  Lion  Head,  3 x j inch,  per  cake..  .50  .03 

2967.  Square,  Black,  Super  Super,  3x  J inch,  per  cak£ 50  .03 

2968.  Square,  Black,  Super  Super,  3f  x f inch,  per  cake...  1.00  .12 

2970.  Oblong,  Black,  Double  Dragon,  fine,  3f  inch, 


per  cake 2.00  .12 

2971.  Oblong,  Dead  Black,  for  Photo-Drawing,  3Jxf 

inch,  per  cake 1.00  .12 

2972.  Oblong,  Red  Ink,  fine,  2f-  inches,  per  cake 75  .03 

2973.  Oblong,  Blue  Ink,  fine,  2f  inches,  per  cake 75  .03 

2974.  Oblong,  Yellow  Ink,  fine,  2f  inches,  per  cake 75  .03 


JAPANESE  INDIA  INK. 

For  drawings  in  which  the  ink-lines  are  washed  in  applying  colors. 


2980. 

No.  Price.  Post. 

2980.  Oblong,  black,  fine  quality,  3f  inches,  small  cake...  $1.00  $0.12 

2982.  Oblong,  black,  fine  quality,  3 J inches,  medium  cake  2.00  .13 

2984.  Oblong,  black,  fine  quality,  3J  inches,  large  cake...  3.00  ,14 


W.  & L.  E.  GURLEY,  TROY,  N.  Y 


385 


WINSOR  & NEWTON’S  WATER-COLORS. 


MOIST  IN  CHINA  PANS,  OR  HARD  COLORS  IN  CAKES. 

(The  moist  colors  are  usually  preferred,  as  they  do  not  waste  by  crumbling.) 


Whole  Cake. 


WIN SOR&  NEWTONS 
MOIST  COLOUR 
38  Rathbone  Place 
LONDON 
SEPIA. 


No. 


Whole  Pan. 


2990.  Whole,  each,  25  cts. ; Half,  each,  15  cts. 


1.  Antwerp  Blue. 

2.  Bistre. 

3.  Blue  Black. 

* 4.  British  Ink. 

* 5.  Bronze. 

6.  Brown  Ochre. 

7.  Brown  Pink. 

8.  Burnt  Sienna. 

9.  Burnt  Umber. 

94.  Charcoal  Gray. 

10.  Chinese  White. 

95.  Chrome  Lemon. 

11.  Uhrome  Yellow. 

12.  Cologne  Earth. 
*48.  Constant  White. 

13.  Deep  Chrome. 


*14.  Dragon’s  Blood. 

15.  Emerald  Green. 

*16.  Flake  White. 

17.  Gamboge. 

18.  Hooker’s  Green  No.  1. 

19.  Hooker’s  Green  No.  2. 

20.  Indian  Red. 

21.  Indigo. 

22.  Italian  Pink. 

23.  Ivory  Black. 

*24.  King’s  Yellow. 

25.  Lamp  Black. 

26.  Light  Red. 

27.  Naples  Yellow. 

28.  Neutral  Tint. 

29.  New  Blue. 


fSOR  8e  NEW TOS 
1/Sr  CO  LOU! 
?dtbbome  Place] 
LONDON 
COBALT 


Half  Pan. 


30.  Olive  Green. 

31.  Orange  Chrome. 

32.  Payne’s  Gray. 

33.  Prussian  Blue. 

34.  Prussian  Green. 

35.  Raw  Sienna. 

36.  Raw  Umber. 

37.  Roman  Ochre. 

38.  Sap  Green. 

39.  Terre  Verte. 

40.  Vandyke  Brown. 

41.  Venetian  Red. 

42.  Vermilion. 

43.  Yellow  Lake. 

44.  Yellow  Ochre. 


2992.  Whole,  each,  45 

*45.  Black  Lead. 

46.  Brown  Madder. 

47.  Cerulean  Blue. 

49.  Crimson  Lake. 
60.  Indian  Yellow. 


cts. ; Half,  each,  25  cts. 

50.  Mars  Yellow. 

51.  Neutral  Orange. 
62.  Orange  Vermilion. 

52.  Purple  Lake, 

53.  Roman  Sepia. 


54.  Reuben’s  Madder. 

55.  Scarlet  Lake. 

56.  Scarlet  Vermilion. 

57.  Sepia. 

58.  Warm  Sepia. 


386 


W.  &>  L.  E.  GURLEY,  TROY,  N.  Y 


No. 

2994.  Whole,  each,  65  cts. ; Half,  each,  35  cts. 


67.  Cadmium  Orange. 

68.  Cadmium  Yellow, 


72.  French  Blue. 

75.  Indian  Purple. 

76.  Intense  Blue. 
61.  Lemon  Yellow, 

77.  Mars  Orange. 


74.  Green  Oxide  of 
Chromium. 


Pale. 


98.  Permanent  Mauve, 

99.  Permanent  Violet. 
79.  Pure  Scarlet 

63.  Violet  Carmine. 


69.  Cadmium  Yellow. 
59.  Cobalt  Blue. 


97.  Cobalt  Green. 


2996.  Whole,  each,  90  cts.;  Half,  each,  45  cts. 


65.  Aureolin. 

91.  Aurora  Yellow. 

66.  Burnt  Carmine. 
70.  Carmine. 


81.  Madder  Carmine. 
78.  Pink  Madder. 

92.  Primrose  Aureolin. 


71.  Field’s  Orange-Ver- 


milion. 


82.  Purple  Madder. 
80.  Rose  Madder. 
90.  Scarlet  Madder. 
93.  Yellow  Carmine. 


2998.  Whole,  each,  $1.40  ; Half,  each,  70  cts. 


83.  Smalt. 


| 84.  Ultramarine  Ash. 


Colors  marked  * are  not  made  in  pans. 

Postage  on  water  colors,  1 cent  each. 

The  following  colors  are  generally  used  by  Architects  and  Civil  and 
Mechanical  Engineers  : 

Burnt  Umber  to  represent  earth. 

Burnt  Sienna  to  represent  wood. 

Light  Red  to  represent  brick. 

Sepia  and  Yellow  Ochre  to  represent  stone. 

Prussian  Blue  to  represent  wrought  iron. 

Payne’ s Gray  to  represent  cast  iron. 

Gamboge  to  represent  brass. 

Gamboge  and  Carmine  to  represent  copper. 

Prussian  Blue  and  Carmine  to  represent  steel. 

In  Topography  the  following  colors  are  generally  used  : 

Hooker’s  Green  No.  2 to  represent  grass. 

Burnt  Sienna  to  represent  cultivated  ground. 

Burnt  Sienna  and  Hooker’ s Green  to  represent  uncultivated  ground. 
Indigo  and  Hooker’s  Green  to  represent  swamp. 

Gamboge  and  Hooker’ s Green  to  represent  trees. 

Yellow  Ochre  to  represent  roads  and  streets. 

Indigo  to  represent  water. 

Carmine  to  represent  buildings,  bridges  and  masonry. 

Sepia  to  represent  hills. 

Sepia  to  represent  shade  lines  and  shadows. 


W.  & L.  E.  GURLEY,  TROY,  N.  Y 


387 


3000.  3010. 


WINSOR  & NEWTON’S  WATER-COLORS. 

IN  POLISHED  MAHOGANY  BOX,  WITH  LOCK  AND  KEY,  AND  DRAWER, 
PAINT-STONE,  WATER-GLASS,  INDIA  INK,  BRUSHES  AND  COLORS. 


No.  Price.  Post. 

3000.  Complete  Box,  with  12  colors,  whole  cakes $9.00  $1.00 

3002.  Complete  Box,  with  18  colors,  whole  cakes 13.50  1.15 

3004.  Complete  Box,  with  12  colors,  half  cakes 6.00  .50 

3006.  Complete  Box,  with  18  colors,  half  cakes 7.75  .65 


• EMPTY  JAPANNED  TIN  COLOR-BOXES. 

3010.  Japanned  Box,  to  hold  6 whole  or  12  half  pans $0.80  $0.06 

3011.  Japanned  Box,  to  hold  9 whole  or  18  half  pans 1.00  .15 

3012.  Japanned  Box,  to  hold  12  whole  or  24  half  pans 1.15  .20 

3014.  Japanned  Box,  to  hold  18  whole  or  36  half  pans 1.40  .26 


EMPTY  WOOD  SLIDE-LID  COLOR-BOXES. 


3015.  Color-Box  to  hold  6 whole  or  half  cakes $0.40  $0.04 

3016.  Color- Box  to  hold  12  whole  or  half  cakes 50  .08 

3017.  Color- Box  to  hold  18  whole  or  half  cakes 60  .12 


388 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 


WATER-COLOR  BRUSHES. 


So10 

« CO 


No. 

3020.  Camel  Hair  in  Quills  : 


No.  1.  2. 

Each,  $0.05  .05 

3. 

.06 

4. 

.06 

5. 

.08 

6. 

.08 

7. 

.10 

8. 

.10 

Post. 

$0.01 

Red  Sable  in  Quills  : 

No.  1.  2. 

Each,  $0.10  .12 

3. 

.15 

4. 

.20 

5. 

.25 

6. 

.33 

7. 

.45 

8. 

.60 

Post. 

$0.01 

3030.  Camel  Hair  in  Tin,  with  handle  : 

No.  1.  2.  3.  4.  5.  6.  Post. 

Each,  |0.10  .10  .12  .12  .15  .15  $0.02 


in 

o 

o 

co 


3035.  Red  Sable,  in  Albata,  with  handle  : 

No.  1.  2.  3.  4.  5.  6.  7.  13.  14.  Post. 

Each,  $0.20  .25.35.45.55.65.75  1.00  1.30  $0.02  to  $0.10 


3040. 


3040. 


Camel  Hair  Sky  or  Wash  Brush,  in  Tin,  with  Handle  : 


No.  0. 
Each,  $0.18 


1.  2.  3.  4. 

.20  .25  .35  .45 


Post. 

$0.02 


W.  & L.  E.  GURLEY,  TROY,  N.  K 


389 


3045. 

3045.  Camel  Hair  Wash  Brushes  in  Tin,  with  two  points  : 

No.  0.  1.  2.  3.  Post. 


Each,  $0.35  .40  .50  .65  $0.02 

WATER-GLASSES,.  INK  AND  COLOR-SLABS. 


3050.  3054. 

No.  Price.  Post. 

3050.  Artist’s  Water-Glass,  2f  inches,  each $0.12  $0.08 

3051.  Artist’s  Water-Glass,  2f  inches,  each 20  .10 

3052.  Artist’s  Water-Glass,  3f  inches,  each 25  .10 

3054.  Ink  or  Color-Slab,  2f  x 1J  inches,  each 10  .05 

3055.  Ink  or  Color-Slab,  3 \ x 2 f inches,  each .15  .07 

3056.  Ink  or  Color- Slab,  4 x2J  inches,  each 25  .10 

3057.  Ink  or  Color-Slab,  4§x2f  inches,  each 30  .15 

3065.  Slate  Ink-Slab,  3J  x 3J  inches,  with  glass  cover,  each  .35  .15 

3067.  Opal  Glass  Ink-Saucer,  with  cover,  3J  inches,  each..  .50  .15 


PATENT  INK-SLAB. 


3070, 


3070.  Patent  Ink-Slab,  China,  with  cover,  4J  x If  inches, 

each $0.35  $0.12 

3071.  Patent  Ink-Slab,  China,  with  cover,  5fx  2^  inches, 

each 40  .16 


390 


W.  & L.  E.  GURLEY,  TROY,  N.  Y 


COLOR-SAUCERS. 


3075. 

No.  Price.  Post. 

3075.  Nest  of  5 Saucers  and  a cover,  2§  inches,  per  nest...  $0.45  $0.15 

3076.  Nest  of  5 Saucers  and  a cover,  2|-  inches,  per  nest...  .55  .20 

3077.  Nest  of  5 Saucers  and  a cover,  3}  inches,  per  nest...  .65  .28 

3078.  Nest  of  5 Saucers  and  a cover,  3f  inches,  per  nest...  .75  .35 


BRASS  STENCILS.  Alphabets  and  Figures. 


No. 

Height  of  Letters  . . 

...  f in. 

1 in. 

h in* 

| in. 

fin. 

1 in. 

3100. 

Stencil- Alphabet. . . . 

..$1.00 

$1.15 

$1.30 

$1.50 

$1.75 

$2.00 

3101. 

Stencil- Alphabet. . . . 

..  1.85 

2.00 

2.15 

2.30 

2.50 

2.75 

3102. 

Stencil- Alphabet. . . . 

..  4.00 

4.15 

4.30 

4.50 

4.75 

5.00 

3103. 

Stencil -Alphabet.... 

..  1.85 

2.00 

2.15 

2.30 

2.50 

2.75 

A set  of  Figures  to  match  any  of  these  Alphabets  will  cost  one-third 
the  price  of  the  same  style  and  size  of  Alphabet. 


Postage  on  each  Alphabet $0. 14 

Postage  on  each  set  of  Figures,  Nos.  3100,  3101  and  3103..  .04 

Postage  on  each  set  of  Figures,  No.  3102 12 

BRASS  STENCIL-PLATES. 

Price.  Post. 

3110.  North  Point,  full  size $0.50  $0.02 

3111.  North  Point,  full  size 75  .02 

3112.  North  Point,  full  size 60  .02 

3115.  Ornamental  Corner,  full  size 1.00  .10 

3116.  Ornamental  Corner,  full  size 75  .03 

3120.  Dasher,  full  size 25  .02 

3121.  Dasher,  full  size 25  .02 


A Stencil-Brush  is  furnished  without  extra  charge. 

Use  thick  India  ink  for  marking. 

Other  styles  and  sizes  of  Alphabets,  Figures  and  Stencil-Plates  made 
to  order. 


JV.  fr  L.  E.  GURLEY,  TROY,  N.  Y. 


391 


STENCIL-PLATES. 


3100.  3101.  3102. 


3103. 


392 


W.  6-  L.  E.  GURLEY, \ TROY,  N.  Y 


COMMON  POCKET-COMPASSES. 


3154.  3160. 


No. 

3150. 

3152. 

3154. 

3155. 

3160. 

3161. 

3164. 

3165. 

3166. 
3168. 


Mahogany  case,  stop  to  needle,  2 inches  square 

Mahogany  case,  stop  to  needle,  3 inches  square 

Government  pattern,  mahogany  case,  3 inches 
square,  raised  ring,  superior  2-inch  needle  with 

stop,  Gurley,  maker 

Compass,  like  No.  3154,  but  3J  inches  square  and 

2J-inch  needle 

Brass,  round,  watch  pattern,  stop  agate  center,  1£ 

inches  diameter 

Brass,  round,  watch  pattern,  stop,  agate  center,  2 

inches  diameter 

Brass,  round,  stop,  agate  center,  1 J inches  diameter, 

with  cover 

Brass,  round,  stop,  agate  center,  2 inches  diameter, 

with  cover 

Brass,  round,  stop,  agate  center,  2J  inches  diameter, 

with  cover  (superior) 

Brass,  round,  watch  pattern,  stop,  agate  center,  1J 
inches  diameter,  with  hinged  cover 


Price. 

$2.00 

2.50 

Post. 

$0.12 

.15 

3.50 

.15 

4.50 

.20 

.85 

.04 

1.00 

.12 

1.10 

.12 

1.25 

.12 

2.50 

•14 

1.25 

.12 

W.  & L.  E.  GURLEY \ TROY,  N.  Y. 


393 


No.  Price.  Post. 

3170.  Brass,  round,  watch  pattern,  stop,  agate  center,  2 

inches  diameter,  with  hinged  cover $1.50  $0.12 


3175. 


3175. 


3170. 


Pocket-Compass,  If  inches  diameter,  hunting-case, 
spring  catch,  stop  to  needle  in  joint  of  cover,  and 

bar  needle  with  agate  center 

Pocket- Compass,  2f  inches  diameter,  hunting-case, 
spring  catch,  stop  to  needle  in  joint  of  cover,  and 
bar  needle  with  agate  center 


3.50 

.12 

4.50 

.12 

3178.  3182. 

3178.  Pocket-Compass,  If  inches  diameter,  watch  pattern, 

gilt,  stem  stop,  bar  needle..' 4.00  .12 


394 


W.  &■>  L.  E.  GURLEY,  TROY , N.  Y 


No.  Price.  Post. 

3182.  Pocket-Compass,  2J  inches  diameter,  with  cover 

folding  sights,  bar  needle  with  agate  center  and 

stop  to  needle $5.50  $0.14 

3183.  Pocket-Compass,  3 inches  diameter,  with  cover, 

folding  sights,  bar  needle  with  agate  center  and 

stop  to  needle 6.50  .16 


3186.  As  Clinometer. 


3186.  Clinometer  Compass,  2£  inches  diameter,  graduated 

to  one  degree,  bar  needle  with  agate  center  and 
stop,  pivoted  sights  to  swing  over  compass-face, 
cover  and  morocco  case 7.25  .15 

3187.  Clinometer  Compass,  3 inches  diameter,  graduated 

to  one  degree,  bar  needle  with  agate  center  and 

stop,  pivoted  sights,  cover  and  morocco  case 8.75  .18 

3188.  Pocket-Compass,  3§  inches  diameter,  heavy  brass 

case  and  cover,  2J-inch  needle  with  agate  center 

and  stop,  superior,  Gurley,  maker 6.00  .20 

3192.  Pocket-Compass,  If  inches  diameter,  watch  pattern, 

stem  stop,  Singer’s  patent  pearl  dial 3.85  .12 

3194.  Geological  Compass,  2f  inches  diameter,  with  pen- 
dulum, for  ascertaining  the  angle  of  dip  in  rocks..  4.25  .15 

3196.  Gilt  Charm  Compasses  to  hang  Price.  Post. 

to  watch  guard $0.25  to  $2.00  $0.02  to  $0.10 

3200.  Pocket-Compass,  watch  pattern,  2|  inches  diameter, 
hunting-case,  raised  ring,  agate  center,  stop  to 
needle,  folding  sights 5.00  .15 


W.  &>  L.  E.  GURLEY,  TROY,  N.  Y 


Price. 


395 


No. 

3220. 


Post. 


Pocket  Alt-Azimuth,  with  Telescope,  for  travelers 
and  military  surveyors.  Altitudes,  azimuths,  com- 
pass bearings,  clinometer  degrees  and  levels  are 
all  obtained  by  this  instrument.  Size  6^  x 2£  x 1 j- 
inches,  in  case $50.00  $0.40 


PRISMATIC  COMPASSES. 


3225. 

No.  Price.  Post. 

3225.  Prismatic  Compass,  2J  inches  diameter,  hunting- 

case  ; can  be  used  as  an  ordinary  compass  without 
opening  the  cover,  and  a prismatic  compass  by 
raising  the  cover,  glazed  with  a stout  glass,  on 
which  is  etched  a line  for  the  sight.  With  folding 
prism  and  floating  card  dial  with  stop $15.00  $0.15 

3226.  Prismatic  Compass,  3J  inches  diameter,  with  float- 

ing metal  dial,  azimuth  glasses,  folding  prism, 
folding  sight  with  hinged  mirror,  ball-joint  and 
staff  socket,  in  morocco  case 21.50  .25 

3227.  Prismatic  Compass,  3 inches  diameter,  with  floating 

card  dial  graduated  to  ^ degrees,  folding  prism 
and  folding  sight,  with  metal  cover,  in  leather 
sling  case 16.00 


.20 


396  . 


W.  & L.  E.  GURLEY,  TROY,  N. . Y 
PRISMATIC  COMPASSES. — Continued. 


3228. 

No.  Price.  Post. 

3228.  Prismatic  Compass,  3 inches  diameter,  with  floating 
metal  dial  divided  to  ^ degrees,  agate  center  with 
stop,  folding  prism  and  folding  sight,  with  metal 

cover  (not  shown  in  cut),  in  leather  sling  case $20.00  $0.20 

3230.  Prismatic  Compass,  Barker’ s Patent,  2f -inch  floating 
dial,  agate  center  with  stop,  mounted  beneath  2j- 
inch  pendulum  dial,  graduated  for  altitudes  0°  to 
180°,  also  graduated  0°  to  90°  both  ways  as  clin- 
ometer and  with  scale  of  rise  or  fall  in  inches  per 
yard ; folding  prism  and  hair  sight,  metal  case 

and  cover,  in  leather  sling  case 27.00  .25 

3232.  Prismatic  Compass,  3 inches  diameter,  with  metal 
dial  graduated  to  J degrees,  agate  center  with 
stop,  folding  prism,  azimuth  glasses,  folding  sight 
with  hinged  and  sliding  mirror,  in  leather  sling 
case 


30.00 


W.  & Z.  E.  GURLEY,  TROY,  N.  Y 


397 


SEXTANTS. 

No.  Prick. 

3240.  Pocket  Sextant  graduated  to  J degrees,  with  vernier 
to  1 minute,  telescope,  two  neutral  glasses,  mag- 
nifier, tangent  screw,  etc.  In  metal  box  3 inches 

diameter,  and  in  morocco  case $42.50 

3245.  Sextant  of  gun-metal,  4J  inches  radius,  arc  of  150° 
graduated  on  silver  to  15  minutes  with  vernier  to 
15  seconds,  clamp  and  tangent  and  magnifier, 
one  terrestrial  telescope,  one  celestial  telescope, 
one  sight-tube,  six  neutral  glasses,  two  mirrors, 

in  mahogany  box 50.00 

3247.  Sextant  of  gun-metal,  6J  inches  radius,  arc  of  150° 
graduated  on  silver  to  10  minutes  with  vernier  to 
10  seconds,  clamp  and  tangent  and  magnifier, 
two  celestial  telescopes,  one  terrestrial  telescope, 
one  sight-tube,  seven  neutral  glasses,  two  mirrors, 
in  mahogany  box 80.00 


3248. 

3248.  Sextant  of  gun-metal,  superior,  7 inches  radius,  arc 
of  150°  graduated  on  silver  to  10  minutes  with 
vernier  to  10  seconds,  clamp  and  tangent  and 
magnifier,  two  celestial  telescopes,  one  terrestrial 
telescope,  one  sight-tube,  seven  neutral  glasses, 
two  mirrors,  in  mahogany  box ,,.100,00 


398 


W.  &>  L.  E.  GURLEY,  TROY,  N.  Y. 


ARTIFICIAL  HORIZONS,  ANGLE- MIRRORS  AND 
PRISMS.  SURVEYORS’  CROSS-STAFF  HEADS. 


No.  Price.  Post. 

3250.  Artificial  Horizon,  with  black  glass  plane  mounted 
in  brass  frame,  with  three  leveling-screws,  and 

sensitive  level-vial.  All  in  mahogany  box $16.00  $0.30 

3252.  Mercurial  Horizon,  iron  trough,  iron  bottle  with 
screw  stopper  and  funnel  cap,  glazed  metal  roof. 

All  in  mahogany  box 37.50 


3256.  3260.  3265. 


3255.  Angle-Mirror,  with  small  plummet,  for  angles  of  90 

degrees.  The  handle  can  be  detached  and 
stored  in  frame  of  instrument.  Size,  2J  x 2 x If 
inches,  in  morocco  case 7.50  .12 

3256.  Angle-Mirror,  plain,  for  angles  of  90°,  in  morocco 

case 5.00  .12 

3260.  Rectangular  Prism,  for  angles  of  90°,  2f  x If  x If 

inches,  in  morocco  case 5.00  .12 

3262.  Double  Prism,  to  take  angles  of  90°  and  45°,  in 

morocco  case 10.00  .12 

3265.  Surveyor’s  Cross-Staff  Head,  for  45°  arid  90° 

angles.  Octagonal,  2J  inches  long.  With  staff 

socket 2.75  .30 

3266.  Surveyor’s  Cross-Staff  Head,  for  45°  and  90° 

angles.  Octagonal,  3 inches  long.  With  magnetic 

compass,  If -inch  needle,  and  with  staff  socket 4.75  .35 

3267.  Surveyor’s  Cross-Staff  Head,  for  45°  and  90° 

angles.  Round,  3f  inches  long.  With  vertical 
axis  graduated  to  1°  and  vernier  to  3 minutes. 

With  magnetic  compass,  2J-inch  needle,  and  with 

staff  socket 11.50  .40 


1 


W.  & L.  E.  GURLEY,  TROY,  N.  K 399 


PEDOMETERS,  PASSOMETERS,  TALLY- 
REGISTER,  AND  ODOMETER. 


3270.  3276. 

No.  Price.  Post. 

3270.  Pedometer,  watch  form.  One  dial  registers  distance 

walked  up  to  12  miles  by  each  J mile $4.50  $0.12 

3272.  Pedometer,  watch  form.  Two  dials  register  distance 

walked  up  to  50  miles  by  each  80  yards 5.25  .12 

3275.  Passometer,  watch  form.  Three  dials  register  each 

step  up  to  25,000  steps 6.00  .12 

3276.  Passometer,  same  as  No.  3275,  but  with  stem  attach- 

ment to  set  the  pointers  to  zero  at  will 7.50  .12 


3282. 


400 


W.  &■  L.  E.  GURLEY,  TROY,  N.  Y. 


No,  Prick.  Post. 

3280.  Tally-Register,  for  surveyors  and  others  ; useful  in 
chaining,  for  counting  persons,  cattle,  coal,  wheat, 
etc.  Registers  to  1,000  and  can  be  set  to  zero  at  will  $2.50  $0.15 

3282.  Veeder  Odometer,  with  fixtures  for  attaching 3.50  .20 

This  Odometer  registers  on  the  dial  every  fifth 
revolution  of  the  carriage  wheel. 

CLINOMETERS. 


3299, 


IV.  &•  L.  E.  GURLEY,  TROY,  N.  Y.  401 

CLINOMETERS. 


No.  Price.  Post. 

3284.  Clinometer  or  Slope-Level  (Gurley,  maker),  7 

inches  long,  arc  to  whole  degrees,  in  wood  case...  $8.00  $0.30 
3288.  Clinometer  or  Slope-Level  (Gurley,  maker),  6 
inches  long,  arc  to  whole  degrees,  two  levels, 

sights  and  staff  mountings,  in  wood  case 16.00  .50 

3290.  Boxwood  Clinometer,  12-inch,  folding  to  6-inch, 
with  two  levels,  compass,  inclination  scale,  and 
sights,  in  leather  case 12.00  .20 


The  inclination  scale  gives  the  value  of  any 
angle.  The  angle,  ascertained  from  the  graduated 
arc,  refers  to  that  degree  in  the  column  marked 
“angle,”  and  another  column  gives  the  rise  or  fall 
in  any  given  distance. 


3292.  Clinometer  or  Slope-Level,  brass  frame,  4 inches 
square,  arc  to  whole  degrees  and  vernier  to  5 
minutes.  The  design  renders  the  measurement  of 
the  inclination  of  the  under  side  of  a plane  avail- 
able, as  any  of  the  four  edges  may  be  used  ; in  case  10,00 


.40 


402 


IV.  6°  L.  E.  GURLEY,  TROY,  N.  K 


ANEROID  BAROMETERS. 

FOR  ASCERTAINING  HEIGHTS,  DIFFERENCES  OF  LEVEL  AND  METEORO- 
LOGICAL CHANGES,  APPROACH  OF  STORMS,  ETC. 

Mountain  Aneroid  Barometers,  compensated  for  temperature,  with 
brass  cases  and  silvered  dials,  in  morocco  cases. 


3303. 


No. 

3300. 

3301. 

3302. 

3303. 

3304. 


Prick.  Post. 

Pocket  Aneroid,  2 inches  diameter,  altitude  scale  to 

3.000  feet,  by  each  10  feet $18.00  $0.20 

Pocket  Aneroid,  2 inches  diameter,  altitude  scale  to 

5.000  feet,  by  each  20  feet 17.00  .20 

Pocket  Aneroid,  2 inches  diameter,  altitude  scale  to 

10.000  feet,  by  each  50  feet 18.00  .20 

Pocket  Aneroid,  2 inches  diameter,  altitude  scale  to 

15.000  feet,  by  each  100  feet 19.00  .20 

Pocket  Aneroid,  2 inches  diameter  (nickeled  hunt- 
ing-case and  omitting  morocco  case)  altitude  scale 

to  6,000  feet,  by  each  50  feet 22.00  .20 


W,  & Z.  E.  GURLEY,  TROY,  N.  Y. 


403 


No. 

3306. 

3308. 

3310. 

3312. 

3314. 

3316. 

3318. 

3322. 

3324. 

3329. 

3330. 
3332. 
3336. 
3338. 

3340. 


Price.  Post. 


Pocket  Aneroid,  2f  inches  diameter,  altitude  scale 
to  10,000  feet,  by  each  60  feet,  with  thermom- 
eter, and  opposite  side  with  pocket-compass $27.00  $0.30 

Pocket  Aneroid,  2f  inches  diameter,  altitude  scale 
to  16,000  feet,  by  each  60  feet,  with  thermom- 
eter and  opposite  side  with  pocket-compass 29.00  .30 

Pocket  Aneroid,  2f  inches  diameter,  altitude  scale 

to  3,000  feet,  by  each  10  feet 19.00  .26 

Pocket  Aneroid,  2|  inches  diameter,  altitude  scale 

to  6,000  feet,  by  each  20  feet 18.00  .26 

Pocket  Aneroid,  2f  inches  diameter,  altitude  scale 

to  10,000  feet,  by  each  60  feet ^ 19.00  .25 

Pocket  Aneroid,  2f  inches  diameter,  altitude  scale 

to  16,000  feet,  by  each  50  feet 20.00  .25 

Pocket  Aneroid,  2f  inches  diameter,  altitude  scale 

to  20,000  feet,  by  each  100  feet 22.00  .25 

Pocket  Aneroid,  2f  inches  diameter,  altitude  scale 
to  10,000  feet,  by  each  50  feet,  and  thermometer..  22.00  .25 

Pocket  Aneroid,  2|  inches  diameter,  altitude  scale 
to  16,000  feet,  by  each  50  feet,  and  thermometer..  23.00  .25 

Pocket  Metric  Aneroid,  2f  inches  diameter,  altitude 
scale  to  1,500  meters,  reading  to  5 meters,  and 


pressure  scale  reading  to  J millimeter 18.00  .25 

Pocket  Metric  Aneroid,  2f  inches  diameter,  altitude 
scale  to  3,000  meters,  reading  to  10  meters,  and 

pressure  scale  reading  to  1 millimeter 19.00  .25 

Pocket  Metric  Aneroid,  2f  inches  diameter,  altitude 
scale  to  5,000  meters,  reading  to  20  meters,  and 

pressure  scale  reading  to  2 millimeters 20.00  .25 

Plain  Aneroid,  no  altitude  scale,  5 inches  diameter, 
with  thermometer  and  open  face  to  show  mechan- 
ism, for  parlor  use 15.00 

Plain  Aneroid,  no  altitude  scale,  6 J inches  diameter, 
and  with  two  thermometers  reading  to  scales  of 
Fahrenheit,  Reaumur  and  Celsius,  and  open  face 

to  show  mechanism,  for  parlor  use 18.00 

Self-Recording  Aneroid  Barometer,  with  attached 
thermometer.  In  mahogany  case  with  glass  front  50.00 


This  barometer  is  used  by  the  U.  S.  Weather 
Bureau,*  and  is  simple  in  construction  and  accurate 
in  its  work.  The  cylinder  makes  a complete  revo- 
lution in  seven  days,  and  thus  each  diagram  gives  a 
barometric  record  for  one  week. 

Note. — The  graduated  spaces  on  the  altitude  scales  of 
Barometers  Nos.  3300  to  3332  can  be  subdivided  by  the  eye  or 
by  using  a magnifier  and  thus  obtain  a closer  reading  than 
advertised. 


404 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y 


SURVEYING  AND  MINING  ANEROIDS. 

-BRONZED  CASES,  SILVERED  DIALS  WITH  REVOLVING  MAGNIFIER.  COM- 
PENSATED FOR  TEMPERATURE.  IN  LEATHER  SLING  CASES. 


No.  Price.  Post. 

3350.  Surveying  Aneroid,  3 inches  diameter,  altitude  scale 
to  6,000  feet,  by  each  20  feet  and  by  vernier  to  2 

feet 142.00  JO.  40 

3352.  Surveying  Aneroid,  3 inches  diameter,  with  altitude 
scale  to  10,000  feet,  by  each  50  feet  and  by  vernier 
to  5 feet 45.00  .40 

3354.  Surveying  Aneroid,  3 inches  diameter,  with  altitude 

scale  to  15,000  feet  by  each  50  feet  and  by  vernier 

to  5 feet 48.00  .40 

3355.  Mining  Aneroid,  3 inches  diameter,  arranged  to 

register  2,000  feet  below  sea-level  to  4,000  feet 

above  by  each  20  feet  and  by  vernier  to  2 feet 42.00  .40 

3360.  Surveying  Aneroid,  5 inches  diameter,  with  altitude 
scale  to  5,000  feet  by  each  10  feet  and  by  vernier 

to  1 foot 50.00 

3362.  Surveying  Aneroid,  5 inches  diameter,  with  altitude 
scale  to  10,000  feet  by  each  20  feet  and  by  vernier 

to  2 feet 52.00 

3364.  Surveying  Aneroid,  5 inches  diameter,  with  altitude 
scale  to  15,000  feet  by  each  20  feet  and  by  vernier 

to  2 feet 54.00 

3366.  Surveying  Aneroid,  5 inches  diameter,  with  altitude 
scale  to  20,000  feet  by  each  50  feet  and  by  vernier 
to  5 feet 57.00 


The  Surveying  and  Mining  Aneroid  has  been  constructed  especially 
for  the  use  of  Surveyors  and  Engineers,  for  ascertaining  slight  variations 
in  gradients,  levels,  etc.,  and  from  its  extreme  sensitiveness  will  be  found 
of  considerable  utility  in  Mining  and  Surveying  work  generally. 

The  Vernier  Scale  is  moved  by  rack  and  pinion,  and  the  magnifier 
which  rotates  on  the  outer  circumference  of  the  instrument  facilities  the 
reading  of  the  vernier. 

A Treatise  on  the  Aneroid  Barometer  ; its  construction  and  use.  Illus- 
trated. 50  cents. 


W.  & L.  E.  GURLEY,  TROY,  N.  K 


405 


TO  USE  THE  ANEROID,  WITH  ALTITUDE 

SCALE. 

Find  the  height  in  feet  at  first  station  and  subtract  this  from  the  height 
in  feet  at  second  station.  If  the  mean  temperature  is  greater  or  less  than 
50°  F. , apply  correction  for  temperature  as  hereafter  given. 

Example : 

Aneroid  at  Station  A,  1800  feet.  Thermometer,  50°. 

Aneroid  at  Station  B,  800  feet.  Thermometer,  70°. 

The  approximate  height  is  1,000  feet.  The  sum  of  the  temperatures  is 
120.  A correction  of  + 20  is  therefore  applied.  This  is  20  feet. 

The  difference  of  elevation  is  therefore  1,000  + 20  = 1,020  feet. 


TO  FIND  THE  RELATIVE  HEIGHT  OF  TWO 
GIVEN  PLACES. 

Take  a reading  of  the  Aneroid  at  first  station  ; subtract  from  this  the 
reading  at  second  station.  The  product  multiplied  by  9 will  give  the 
difference  of  altitude  in  feet  thus  : 

First  Station,  30.20  ; Second  Station,  29.99  ; 30.20  — 29.99  = .21  ; 

.21  x 900  (or  21  x 9)  = 189  feet  = difference  of  altitude. 

This  under  ordinary  pressures  and  with  a temperature  about  50°  F. 
will  give  good  results.  If  the  temperature  is  over  70°  F.  multiply  by  10. 
The  table  prepared  by  Mr.  Symons  is  more  strictly  accurate  : 


Mean  Temperature. 

30° 

40° 

50° 

60° 

70° 

80° 

Mean  pressures,  27  inches... 

9.7 

9.9 

10.1 

10.3 

10.5 

10.8 

Mean  pressures,  28  inches... 

9.3 

9.5 

9.8 

10.0 

10.2 

10.4 

Mean  pressures,  29  inches... 

9.0 

9.2 

9.4 

9.6 

9.8 

10.0 

Mean  pressures,  30  inches... 

8.7 

8.9 

9.1 

9.3 

9.5 

9.7 

Roughly  speaking,  the  barometer  falls  one  inch  for  every  900  feet  of 
ascent ; or  at  mean  atmospheric  pressure  in  this  latitude, 


Above  sea-level  917  feet,  the  barometer  falls 1 inch. 

Above  sea-level  1860  feet,  the  barometer  falls 2 inches. 

Above  sea-level  2830  feet,  the  barometer  falls 3 inches. 

Above  sea-level  3830  feet,  the  barometer  falls 4 inches. 

Above  sea-level  4861  feet,  the  barometer  falls 5 inches. 


406 


W.  & L.  E.  GURLEY,  TROY,  N.  K 


ANEMOMETERS. 

FOR  MEASURING  THE  PRESSURE  AND  VELOCITY  OF  CURRENTS  OF  AIR  IN 
COAL  MINES,  AND  VENTILATORS,  FLUES,  ETC.,  OF  PUBLIC  BUILDINGS. 

“Biram’s.” — For  registering  the  velocity  of  currents  of  air  in  mines, 
tunnels,  etc.,  by  means  of  a light  fan,  the  revolutions  of  which  are 
recorded  on  a dial  in  the  center  of  the  instrument. 

This  instrument  placed  in  the  passage  of  a mine  registers  automatically 
the  rate  at  which  the  air  is  traveling  through  it,- and  a simple  observation 
will  detect  any  slackening  of  the  current  arising  from  obstruction  of  the 
ways,  or  want  of  attention  at  the  ventilating  furnace,  or  fan-wheel. 


No. 

3380. 

3382. 

3384. 

3386. 


3330. 


hram’ s Anemometer,  3 inches  diameter,  reading  to 

1,000  feet,  with  disconnector,  in  morocco  case.  ...$19.00 
liram’s  Anemometer,  4 inches  diameter,  reading  to 

1,000  feet,  with  disconnector,  in  wood  case. 

3iram’ s Anemometer,  6 inches  diameter,  reading  to 

1,000  feet,  with  disconnector,  in  wood  case.. 

Biram’s  Anemometer,  6 inches  diameter,  reading  to 


Price.  Post. 


|0.30 


19.00 

.40 

20.00 

.60 

22.00 

.60 

W.  & L.  E.  GURLEY,  TROY,  N.  Y 


407 


No.  Price.  Post. 

3388.  Biram’s  Anemometer,  6 inches  diameter,  reading  to 

10,000,000  feet,  with  disconnector,  in  wood  case..$30.00  $0.60 
3390.  Biram’s  Anemometer,  watch  pattern,  hunting-case, 

very  sensitive,  reading  to  1,000  feet 26.00  .18 

Pocket  Size  [2  inches  diameter ) — Is  made  in  the  form  of  a watch  — 
the  top  and  bottom  of  the  case,  when  opened,  form  a base  for  the  instrument, 
a check-spring  passing  through  the  pendant  acts  as  a stop  to  the  movement, 
on  being  pressed  by  the  finger  at  the  expiration  of  the  time  necessary  to 
make  the  observation.  The  movement  is  jeweled  at  four  points.  The 
outer  circle  of  divisions  on  the  dial  records  by  single  feet  up  to  one  hun- 
dred ; the  smaller  dial  continues  the  enumeration  up  to  one  thousand  feet. 


HOW  TO  USE  THE  ANEMOMETER. 

The  Anemometer  consists  of  a series  of  vanes,  which  revolve  with  the 
action  of  the  air-current,  the  number  of  revolutions,  or  numbers  propor- 
tioned to  the  revolutions,  being  registered  by  a pointer  on  the  face  of  a dial, 
forming  part  of  the  instrument  itself.  An  observer  has  only  to  record  the 
position  of  the  several  indices  at  the  first  observation  (by  writing  the  lower 
of  the  two  figures  on  the  respective  circles,  between  which  the  index 
points,  in  their  proper  order),  and  deduct  the  amount  from  their  position 
at  the  second  observation,  to  ascertain  the  velocity  of  the  air  which  has 
passed  in  the  interval.  This  multiplied  by  the  area  in  feet  of  the  passage, 
where  the  instrument  is  placed  will  show  the  number  of  cubic  feet  which 
has  passed  during  the  same  period. 

Thus,  suppose  the  observation  of  one  minute  gives  : 


Second  reading 525 

First  reading * '..  225 

300 

Add  correction,  say 30 

330 


Size  of  passage  in  feet,  10  x 5 x 330  16,500  feet  per  minute. 

The  correction  added  above  is  the  value  of  the  constant  of  friction, 
which  must  be  found  for  each  machine  by  actual  experiment. 


TO  FIND  THE  VELOCITY  OF  THE  AIR  IN  THE  PASSAGE. 

Proceed  thus  : Suppose  the  Anemometer  indicates  330  feet  per  minute. 
330  -s-  88  = 3.75,  or  3f  miles  per  hour,  88  being  ^th  of  a mile. 

To  ascertain  the  force  of  the  air-current,  multiply  the  square  of  the 
velocity  of  the  air  in  feet  per  second  by  .0023. 


408 


IV.  & L.  E.  GURLEY, , TROY,  JY.  Y. 


AIR-METERS. 


3397. 


No.  Price.  Post. 

3396.  Air-Meter,  with  disconnector,  fan-wheel  2J  in. 

diameter,  two  dials  reading  to  1,000  feet .......$  19.00  $0.35 

3397.  Air-Meter,  with  disconnector,  fan-wheel  2f  in. 

diameter,  six  dials  reading  to  10,000,000  feet.....  21.00  .35 

The  portable  “ Air- Meter”  is  for  the  measurement  of  currents  of  air 
through  mines,  tunnels,  sewers  and  the  ventilators  of  hospitals,  public 
buildings,  etc.  The  indications  are  obtained  by  means  of  a delicately 
poised  fan-wheel,  the  recordings  being  commenced  by  the  long  hand, 
which  traverses  the  extreme  outer  circumference  of  the  main  dial  for  the 
passage  of  one  hundred  feet  of  air.  The  enumeration  is  continued  up  to 
ten  millions  of  feet  (say  1,894  miles),  by  a series  of  smaller  dials  as 
shown  in  the  illustration.  A “ Disconnector  ” projecting  from  the  band 
of  the  instrument,  opposite  the  fan-wheel,  serves  to  throw  the  mechanism 
out  of  gear,  and  arrest  its  action,  when  required.  The  instrument  is 
packed,  with  universal  jointed  socket-holder,  in  a box  about  four  inches 
square. 


NO.  3400.  NO.  3442  with  focusing  attachment. 

FIELD-GLASS,  GOOD  QUALITY. 


No.  Price.  Post. 

3400.  Body,  4J  inches  long  ; object-glasses,  21  lines $7.00  $0.30 

3402.  Body,  6J  inches  long  ; object-glasses,  26  lines 9.00  .40 

FIELD-GLASS,  FINE  QUALITY. 

3407.  Body,  5£  inches  long  ; object-glasses,  24  lines 14.00  .45 

3408.  Body,  6J  inches  long  ; object-glasses,  26  lines 15.00  .50 

JENA  FIELD-GLASS. 

(new  style  and  superior.) 

3410.  Body,  6 inches  long  ; object-glasses,  26  lines 16.00  .50 

3411.  Body,  5§  inches  long  ; object-glasses,  24  lines  and 

with  hing'e  adjustment 18.00  .45 

U.  S.  ARMY  SIGNAL  SERVICE  FIELD-GLASS. 

(VERY  SUPERIOR.) 

3413.  Body,  6f  inches  long  ; object-glasses,  24  lines 18.00  .45 

3414.  Body,  6f  inches  long  ; object-glasses,  26  lines 20.00  .50 

3416.  Body,  6§  inches  long  ; object-glasses,  24  lines  and 

with  hinge  adjustment 20.00  .45 

3417.  Body,  6f  inches  long;  object-glasses,  26  lines  and 

with  hinge  adjustment 23.00  .50 


TV.  L.  E.  GURLEY,  TROY,  N.  Y.  409 


FIELD-GLASSES  AND  BINOCULAR  TELESCOPES. 

The  Field-Glasses  here  described  are  of  the  best  quality  and  especially 
adapted  for  tourists,  engineers,  military  service,  or  general  field  use.  They 
are  achromatic,  and  are  metal  body  covered  with  morocco,  and  have  a 
case  with  strap.  Some  are  designated  by  the  diameter  of  the  object- 
glasses  in  French  lines,  eleven  lines  being  equal  to  one  inch. 


410  W.  & L.  E.  GURLEY,  TROY,  N.  Y. 

GOERZ-TRIEDER-BINOCULAR. 

(new  style,  great  power.) 

No.  - Price.  Post. 

8418.  Trieder-Binocular,  No.  80,  power  9 times $54.00  $0.35 

3419.  Trieder-Binocular,  No.  40,  power  12  times 62.00  .40 

BINOCULAR  TELESCOPE. 

(old  pattern.  ) 

3422.  Body,  5J  inches  long ; object-glasses,  8 lines ; 

power  10  times 27.00  .35 

3423.  Body,  9J  inches  long ; object  glasses,  16  lines  ; 

power  16  times 45.00  .75 

3424.  Body,  11  inches  long;  object  glasses,  19  lines; 

power  20  times 50.00  .90 

JENA  BINOCULAR  TELESCOPE. 

These  binoculars  have  great  power,  a hinge  ad- 
justment, and  a device  for  quick  focusing. 

3426.  Body,  6f  inches  long;  object-glasses,  11  lines; 

power  18  times 36.00  .60 

3428.  Body,  7J  inches  long;  object  glasses,  15  lines;  . 

power  24  times 45.00  .75 

RANCHMAN'S  GLASS. 

(superior  quality.) 

3430.  Body,  6f  inches  long  ; object-glasses,  26  lines 18.00  .50 

PANERGETIC  GLASS. 

(aluminum  body,  new  style  and  superior.  ) 

3434.  Body,  4 inches  long ; object-glasses,  21  lines 23.00  .30 

3435.  Body,  4\  inches  long  ; object  glasses,  24  lines 26.00  .35 

3438.  Body,  4^  inches  long;  object-glasses,  24  lines  and 

with  hinge  adjustment 31.00  .35 

IMPROVED  OPERA  AND  FIELD-GLASS. 

This  glass  has  a double  draw  to  the  eye  end, 
like  a telescope. 

3440.  Body,  Sc  inches  long;  object-glasses,  17  lines 15.00  0.30 

3441.  Body,  4 inches  long ; object-glasses,  19  lines 16.00  .35 

BAUSCH  & LOMB-ZEISS  STEREO  BINOCULAR. 

(latest  style  and  superior.) 

3442.  Stereo  Binocular,  No.  8,  power  8 times 58.00  0.35 

3443.  Stereo  Binocular,  No.  12,  power  12  times 80.00  .40 

If  with  focusing  attachment,  as  shown,  add 
$5.00  extra. 

BAUSCH  & LOMB  PLAIN  BINOCULAR. 

(superior  quality.) 

3446.  Plain  Binocular,  No.  8,  power  8 times 40.00  0.35 

3447.  Plain  Binocular,  No.  10J,  power  10J  times 48.00  .40 

If  with  focusing  attachment,  add  $5.00  extra. 


iv.  & L.  E.  GURLEY,  TROY,  N.  Y.  411 

ACHROMATIC  TELESCOPES. 


* 3475. 

Price.  Post. 

5475.  Telescope,  with  3 draws,  15  inches  drawn  out,  6 

inches  shut,  object-glass  1 inch  in  diameter,  power 

13  times........ 12.50  #>.20 

5476.  Telescope,  with  3 draws,  16  inches  drawn  out,  6 

inches  shut,  object-glass  If  inches  in  diameter, 

power  16  times 3.60  .25 

5477.  Telescope,  with  3 draws,  23  inches  drawn  out,  8 

inches  shut,  object-glass  If  inches  in  diameter, 

power  20  times 5*00  .30 

5478.  Telescope,  with  3 draws,  30  inches  drawn  out,  10 

inches  shut,  object-glass  If  inches  in  diameter, 

power  25  times 7.00  .40 

3479.  Telescope,  with  4 draws,  37  inches  drawn  out,  11 
inches  shut,  object-glass  If  inches  in  diameter, 

power  35  times 10.00  .65 

3480/  Telescope,  with  4 draws,  42  inches  drawn  out,  Ilf 
inches  shut,  object-glass  2J  inches  in  diameter, 

power  40  times * 17.00  .85 

3481.  Telescope  with  4 draws,  48  inches  drawn  out,  13f 
inches  shut,  object-glass  2f  inches  in  diameter, 
power  50  times 30.00 


412  W.  &>  L.  E.  GURLEY,  TROY,  N.  Y. 

TOURISTS’  ACHROMATIC  TELESCOPES. 


No.  Price.  Post. 

3485.  Telescope,  with  brass  body  covered  with  morocco  ; 

three  draws,  17  inches  drawn  out,  6 inches  shut ; 
object-glass  If  inches  in  diameter ; sun-shade  ; 
leather  caps  to  cover  eyepiece  and  object-glass 
and  shoulder  strap.  Power  20  times $8.00  $0.20 

3486.  Telescope,  same  as  No.  3485,  but  is  21  inches 

drawn  out,  7 inches  shut ; object-glass  If  inches 

in  diameter.  Power  25  times 11.00  .30 

3487.  Telescope,  same  as  No.  3485,  but  is  24  inches 

drawn  out,  9 inches  shut ; object-glass  If  inches 

diameter.  Power  30  times 15.00  .40 

3488.  Telescope,  same  as  No.  3485,  but  has  four  draws, 

36  inches  drawn  out,  10  inches  shut ; object-glass 

2 inches  in  diameter.  Power  35  times 22.00  .60 

3492.  Rifle  Spy-glass,  lOf  inches  drawn  out ; body  covered 
with  morocco;  object-glass  J-inch  in  diameter. 

Power  10  times 2.50  .15 

3494.  Wooden  Tripod  Stand,  with  vertical  and  horizontal 
motion,  upon  which  to  place  a telescope  ; a useful 
article,  as  a telescope  of  much  power  can  not  be 

held  in  the  hand  with  sufficient  steadiness 5.00 

3496.  Brass  Clamp  with  Gimlet  Screw,  to  fasten  a tele- 
scope to  a post  or  tree  ; four  sizes  to  fit  telescopes 
Nos.  3475  to  3488.  Price  according  to  size 
$1.50,  2.00,  2.50  and  3.50  .15 


ASTRONOMICAL  TELESCOPES. 

Price. 

3502.  Astronomical  Telescope,  polished  brass  body,  35 
inches  long,  mounted  on  brass  tripod  stand,  achro- 
matic object-glass  2f  inches  in  diameter,  one  ter- 
restrial eyepiece,  power  50  times,  one  celestial 
eyepiece,  power  100  times,  rack  and  pinion  for 

focusing.  In  box  with  lock $75.00 

3506.  Astronomical  Telescope,  polished  brass  body,  35 
inches  long,  rack  and  pinion  for  focusing,  achro- 
matic object-glass,  2J  inches  in  diameter,  ter- 
restrial eyepiece,  power  40  times,  celestial  eye- 
piece with  darkener,  power  80  times,  wooden 
tripod  with  horizontal  and  vertical  motion.  In  box 
with  lock,  for  receiving  the  body  and  eyepieces...  75.00 
3508.  Astronomical  Telescope.  Same  as  No.  3506,  but 
with  body  40  inches  long,  achromatic  object-glass 
3 inches  in  diameter,  terrestrial  eyepiece,  power 
55  times,  celestial  eyepiece  with  darkener,  power 
110  times.  In  box  with  lock ,,,,,.,.100,00 


IV.  & L.  E.  GURLEY,  TROY,  N.  V 413 

POCKET  MAGNIFIERS. 


3520. 

RUBBER  CASE,  OVAL  FORM 

No.  Prick.  Post. 

3520.  1-inch $0.40  $0.02 

3521.  lj-inch 60  .02 

RUBBER  CASE,  OVAL  FORM, 

3526.  | and  1-inch.... $0.65  $0.03  | 


3526. 


, 1 DOUBLE-CONVEX  LENS. 

No.  Price.  Post. 

3522.  If  inch $0.70  $0.03 

3523.  2-inch 1.15  .12 

2 DOUBLE-CONVEX  LENSES. 

3528.  ljand  If  inch.$1.10  $0.12 


3530. 


RUBBER  CASE,  BELLOWS  FORM,  1 DOUBLE-CONVEX  LENS. 

3530.  |-inch $0.40  $0.02  | 3532.  1-inch $0.60  $0.02 

RUBBER  CASE,  BELLOWS  FORM,  2 DOUBLE-CONVEX  LENSES. 

3534.  j and  f-incb..$0.60  $0.02  | 3536.  f and  l-inch,.$1.00  $0.12 


414  w.  L.  E.  GURLEY,  TROY,  N.  Y. 

RUBBER  CASE.  BELLOWS  FORM,  3 DOUBLE-CONVEX  LENSES. 

No.  Price.  Post.  No.  Price.  Post. 

3538.  },  f and  f-inch$0.80  $0.03  3539.  f,  and  1-inch  $1.30  $0.12 


3542.  White  Celluloid  Case,  oval  form,  one  1-inch  double- 

convex  lens $0.75  $0.02 

3546.  Aluminum  Case,  oval  form,  one  1-inch  double- 

convex  lens 75  .02 

3550.  German  Silver  Case,  oval  form,  one  1-inch  double- 

convex  lens 60  .04 

3555.  Microscope,  brass  mounted,  on  three  legs  adjustable.  .75  .05 


3560. 


3560.  Linen  Prover,  for  counting  threads  in  linen  fabrics, 

brass  mounted,  J-inch  square  open  space 50  .02 

3561.  Linen  Prover,  for  counting  threads  in  linen  fabrics, 

brass  mounted,  j^-inch  round  open  space 50  .02 

3562.  Linen  Prover,  for  counting  threads  in  linen  fabrics, 

brass  mounted,  j^-inch  round  and  J-inch  square 

open  spaces 60  .02 

3565.  Linen  Prover,  for  counting  threads  in  linen  fabrics, 

brass  mounted,  1 -inch  square  open  space 1.75  .13 

3566.  Coddington  Lens,  brass  mounted,  small 1.00  .12 

3567.  Coddington  Lens,  brass  mounted,  medium 1.35  .14 

3568.  Coddington  Lens,  brass  mounted,  large 1.75  .15 

3569.  Aplanatic  Magnifier,  high  power,  and  flat  field 1.00  .12 


3570. 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y.  415 

No.  Price.  Post. 

3570.  Coddington  Lens,  nickeled  frame  and  cover,  J-inch 

diameter $1.50  $0.12 

3571.  Coddington  Lens,  nickeled  frame  and  cover,  f-inch 

diameter 1.75  .12 

3572.  Coddington  Lens,  nickeled  frame  and  cover,  1-inch 

diameter  i 2.00  .12 

3575.  Aplanatic  Triplet,  nickeled  frame  and  cover,  supe- 
rior quality,  giving  perfect  definition,  J-inch  focus, 

power  20  tunes 6.00  .12 

3577.  Aplanatic  Triplet,  nickeled  frame  and  cover,  supe- 
rior quality,  giving  perfect  definition,  1-inch  focus, 

power  10  times 6.00  .12 

Lenses  Nos.  3566  to  3577  have  extra  power 
and  definition  for  examining  minerals,  ore,  rock, 
flowers,  etc. 


READING-GLASSES. 


READING-GLASS,  MEXAL  FRAME,  DOUBLE- CONVEX  LENS. 


No. 

Price. 

Post. 

No. 

Price. 

Post. 

3585. 

2 inches  diam..$0.80 

$0.05 

3589. 

4 inches  diam..$2.50 

$0.18 

3586. 

2 J inches  diam  1.00 

.13 

3591. 

5 inches  diam..  4.00 

.35 

3587. 

3 inches  diam..  1.50 

.15 

3593. 

6 inches  diam..  6.00 

.40 

READING-GLASS,  METAL 

FRAME,  TWO  PLANO-CONVEX  LENSES. 

3595. 

2 inches  diam..  1.25 

.15 

3597. 

3 inches  diam..  2.25 

.20 

3596. 

2 J inches  diam  1.50 

.18 

3598. 

3 J inches  diam  3.25 

.25 

READING-GLASS,  OBLONG 

METAL 

FRAME, 

DOUBLE- CONVEX  LENS. 

3600. 

2|  x 1J  inches..  1.50 

.13 

3602. 

3}  x 1J  inches..  2.00 

.18 

3601. 

3 xl|  inches..  1.75 

,15 

3603, 

3J  x If  inches..  2.50 

.20 

416 


W.  <5r*  L.  E.  GURLEY,  TROY,  N.  Y. 


POCKET  SPIRIT-LEVELS.  (French  Make.) 

PLAIN  VIALS,  MOUNTED  IN  BRASS. 


No.  Price.  Post. 

3650.  3 inches $0.50  $0.06 

3651.  6 inches 1.00  .18 


No.  Price.  Post. 

3652.  9 inches $1.50  $0.23 

3653.  12  inches 2.00  .28 


POCKET  SPIRIT-LEVELS. 

* 

A superior  article.  Our  own  make,  with  ground  and  graduated  vial, 
mounted  in  brass  and  adjustable. 


3660. 


3660.  6 inches $3.00  $0.18  | 3664.  10  inches $4.00  $0.25 

LEVEL- VIALS,  UNMOUNTED. 

OUR  OWN  MAKE,  AND  EVERYONE  TESTED. 


3675. 


3675. 


3690. 


3710. 


Ground  and  Graduated  Level-Vials,  unmounted  : 


U inches 

$0.45 

2 inches... 

...$0.50 

2J  inches 

.$0.60 

3 inches 

. .75 

3J  inches... 

...  .90 

4 inches 

. 1.05 

4J  inches 

. 1.20 

5 inches... 

...  1.45 

5J  inches 

. 1.65 

6 inches 

. 1.80 

6J  inches... 

...  2.00 

7 inches 

. 2.25 

Ground  Level-Vials,  not  graduated,  nmmounted  : 

1 to  1}  inches. 

. .35 

2 inches... 

...  .40 

2J  inches 

. .50 

3 inches 

. .60 

3J  inches... 

...  .75 

4 inches 

..  .90 

44  inches 

. 1.00 

5 inches... 

...  1.25 

5J  inches 

. 1.40 

6 inches 

. 1.50 

6J  inches... 

...  1.65 

7 inches 

. 1.85 

Plain  Level-Vials,  not  graduated,  unmounted 

: 

1 to  1 J inches. 

. .10 

2 inches... 

...  .12 

2^  inches 

. .13 

3 inches 

. .15 

3J  inches... 

...  .18 

4 inches 

. .20 

4J  inches 

. .25 

5 inches... 

...  .35 

5J  inches 

. .40 

6 inches 

. .50 

64  inches... 

...  .60 

7 inches 

. .75 

Note.— If  sent  by  mail,  the  postage  on  unmounted  level-vials  1%  to  7 
inches,  will  be  3 cents  to  18  cents,  according  to  size. 

When  ordering,  mention  the  length  and  diameter  required. 


417 


IV.  & L.  E.  GURLEY,  TROY,  N. 


Y. 


CARPENTERS’  AND  MASONS’  SPIRIT-LEVELS. 


No.  Price. 

3726.  Cherry  Body,  26  inches  long,  with  level  and  plumb  vials..  $0.75 

3727.  Cherry  Body,  28  inches  long,  with  level  and  plumb  vials..  .85 

3730.  Cherry  Body,  26  inches  long,  brass  ends,  both  vials  ad- 

justable  1.25 

3731.  Cherry  Body,  28  inches  long,  brass  ends,  both  vials  ad- 

justable  1.35 

3734.  “ Handy”  Plumb  and  Level,  cherry  body,  26  inches  long, 

brass  ends,  adjustable  vials 1.50 

3738.  Mahogany  Body,  28  inches  long,  brass  ends,  adjustable  vials  1.75 

3740.  Iron  Frame,  22  inches  long,  adjustable  vials.  Superior 3.50 


3765. 

3766. 

3768. 

3773. 

3775. 


OILSTONES. 

Price. 

Arkansas  Oilstones,  fine  quality  for  drawing-pens $0.25 


Arkansas  Oilstones,  fine  quality,  3 \ x 1 inches,  in 

mahogany  block  with  cover 75 

Arkansas  Oilstones,  fine  quality,  5x2  inches,  in 

mahogany  block  with  cover 2.00 

Washita  Oilstones,  common,  3 J x 1 inches,  in  cherry 

block  with  cover '. 45 

Washita  Oilstones,  common,  5x2  inches,  in  cherry 

block  with  cover 75 


Post. 

$0.03 

.10 

.25 

.10 

.20 


418 


IV.  & L.  E.  GURLEY,  TROY,  N.  Y. 


No.  Priced  Post. 

3780.  Trammel  Points,  small,  No.  1,  see  page  411 §1.00  §0.15 

3781.  Trammel  Points,  medium,  No.  2 1.25  .20 

3782.  Trammel  Points,  large,  No.  3 1.65  .25 


3800.  Machinists’  Tools,  Lathe  and  Drill -Chucks  and 
Drills,  Steel  Squares  and  Gauges,  Brass  Tubing 
and  Wire,  Sheet  Brass  and  German  Silver,  Stubs’ 
Steel  Wire,  etc.,  etc.,  at  manufacturers’  prices. 


STEEL  MAGNETS. 


3850. 


No. 

Price. 

Post. 

No. 

Price. 

Post. 

3850. 

2 inches — 

..  §0.12 

§0.03 

3856. 

5 inches 

..  §0.50 

§0.10 

3852. 

3 inches.... 

..  .20 

.04 

3858. 

6 inches 

.75 

.13 

3854. 

4 inches — 

..  .35 

.06 

3860. 

7 inches — 

..  1.10 

.20 

BRASS  BLOW-PIPES. 


3865. 

3867. 

3869. 


PLAIN. 

8 inches 

10  inches 

12  inches 


§0.15  §0.05 
.20  .06 

.25  .07 


WITH  BULB. 

3875.  8 inches §0.30  §0.05 

3877.  10  inches 35  .06 

3879.  12  inches 40  .07 


THERMOMETERS  IN  JAPANNED  CASES. 

( OPEN  AIR  SCALE.  ) 

COMMON.  FINE  QUALITY. 


3890. 

6 Ihches... 

..  §0.30 

§0.06 

3900. 

7 inches... 

..  §0.50 

§0.08 

3892. 

8 inches... 

..  .40 

.10 

3901. 

8 inches... 

..  .65 

.12 

3894. 

10  inches.... 

..  .55 

.12 

3903. 

10  inches... 

..  .85 

.15 

3896. 

12  inches..., 

.18 

3905. 

12  inches.... 

..  1.00 

.25 

3910.  8 inches,  fine  quality  with  boiling  scale 75  .12 

3912,  10  inches,  fine  quality  with  boiling  scale 1.00  .25 


3910.  8 inches,  fine  quality  with  boiling  scale 75  .12 

3912,  10  inches,  fine  quality  with  boiling  scale 1.00  .25 


IV.  & L.  E.  GURLEY \ TROY,  N.  Y. 


419 


THERMOMETERS  WITH  FANCY  WOOD  BACKS. 

(open  air  scale.  ) 


OAK  BACK. 

MAHOGANY  BACK. 

No. 

Price.  Post. 

No. 

Price. 

Post. 

3920. 

8 inches $1.00  $0.18 

3930.  8 inches 

$1.15 

$0.18 

3922. 

10  inches 1.25  .20 

3932.  10  inches 

1.35 

.20 

3924. 

3935. 

12  inches 1.50  .25 

Pocket  Thermometer,  folding 

wood  case,  6J-inch... 

1.00 

.15 

3938. 

Pocket  Thermometer,  in  metal  tube,  nickel-plated, 
5-inch 

.85 

.12 

3940. 

Window  Thermometer,  8-inch,  plate -glass,  white 
face,  with  brackets. 

1.50 

.25 

3943. 

Brewers’  Copper  Case  Thermometer,  12-inch,  and 
deep  cup 

2.50 

.30 

3945. 

Dairy  Thermometer,  all  glass 

.,  floating,  8-inch 

.35 

.07 

3950. 

Chemical  Thermometer,  all 
14-inch 

glass,  60°  to  300°, 

4.00 

.25 

3952. 

Chemical  Thermometer,  all 
14-inch 

glass,  60°  to  400°, 

4.50 

.25 

3954. 

Chemical  Thermometer,  all 
14-inch 

glass,  60°  to  500°, 

5.00 

.25 

SELF-REGISTERING  THERMOMETERS. 


No.  Price.  Post. 

3960.  Maximum  Thermometer,  10-inch,  wood  back $2.75  $0.20 

3962.  Maximum  Thermometer,  U.  S.  Weather  Bureau 

pattern,  12-inch,  aluminum  back 5.00  .20 

3965.  Minimum  Thermometer,  10-inch,  wood  back 2.25  .20 

3967.  Minimum  Thermometer,  U.  S.  Weather  Bureau 

pattern,  12-inch,  aluminum  back 4.25  .20 

3970.  U.  S.  Weather  Bureau  set  of  Maximum  and  Mini- 
mum Thermometers,  12-inch,  aluminum  back, 
and  mounted  together  on  one  wood  back 9.50  .50 


3975.  Mason’s  Hygrometer,  consisting  of  dry  and  wet  bulb 

thermometers  mounted  on  one  wood  back,  7-inch,  2.50  .30 


All  these  Thermometers  have  the  Fahrenheit  scale. 


420 


W.  & L.  E.  GURLEY,  TROY,  N.  Y. 


RAIN-GAUGES. 

Price. 

Smithsonian  Rain-Gauge,  made  of  brass.  This 
gauge  is  the  most  simple  in  its  construction  of  any 
now  in  use.  It  is  furnished  with  a measuring- 
stick  which  reads  to  lOths  and  lOOths  of  inches  ; 
also  a wooden  cylinder  to  insert  in  the  ground 
for  the  protection  and  ready  adjustment  of  the  in- 
strument  ..  $5.00 

U.  S.  Weather  Bureau  Standard  Rain  and  Snow- 
Gauge,  8-inch  diameter,  25J-inch  high,  with 

measuring- stick 6.00 

Howard’s  Rain-Gauge,  consisting  of  a vertical  glass 
bottle,  through  the  neck  of  which  the  terminal 
tube  of  a galvanized  iron  funnel,  5 inches  in  diam- 
eter, is  inserted.  A glass  graduate,  measuring  to 
lOOths  of  an  inch,  is  furnished  with  the  instru- 
ment  4.00 


HYDROMETERS. 

(with  baume’s  scale.) 

Price. 

3990.  Hydrometers,  for  testing  Acid,  Alkalies,  Ammonia, 

Bark,  Beer,  Ether,  Milk,  Molasses,  Oils,  Salt 

Water,  Spirits,  Syrup,  Urine,  Vinegar.  Each $0.75 

3995.  Twaddel’s  Hydrometers,  Nos.  1 to  6 with  scales 
respectively  0 to  24,  24  to  48,  48  to  72,  72  to  100, 

100-  to  134,  134  to  180,  each  graduation  repre- 
senting five  degrees  of  specific  gravity.  Each 75 


No. 

3980. 

3981. 

3982. 


Post 

$0.10 

10 


SCIENTIFIC  BOOKS 

FOR  SALE  BY 

W.  & L.  E.  GURLEY, 

TROY,  N.Y., U.  S.  A. 


Architecture,  Carpentry  and  Building,  Astronomy,  Bridges, 
Roofs  and  Tunnels,  Chemistry  and  Physics,  Construction, 
Strength  of  Materials,  Drawing,  Electricity  and  Telegra- 
phy, Geology,  Mining  and  Metallurgy,  Hydraulic  and 
Sanitary  Engineering,  Machinery  and  Mechan- 
ics, Pocket  Table-Books,  Surveying  and 
Engineering-Instruments,  Etc. 


NOTE. — Parties  ordering  should  either  send  drafts  on 
New  York,  or  postal  orders  on  Troy,  N.  Y. ; or  if  money  is 
enclosed  in  letters,  such  letters  should  be  registered  at  the 
post-office  where  mailed. 

We  prepay  postage  on  nearly  all  American  and  English 
Books  when  the  price  is  sent  to  us  in  advance. 

Books  can  be  registered  at  an  extra  cost  of  eight  cents 
for  each  package  of  not  over  four  pounds. 

Orders  for  over  $10  will  be  sent  by  express/4  C.  O.  D.” 
if  desired  ; but  for  smaller  sums,  parties  will  please  remit 
the  necessary  amount  with  their  order. 

Write  all  letters  legibly,  give  your  Post-office,  County 
and  State,  and  be  sure  to  sign  your  letter  before  mailing. 

We  are  not  responsible  for  loss  of  goods  sent  by  mail. 

Should  any  other  works  on  kindred  topics  be  desired, 
we  will  furnish  them  at  publishers’  prices. 

Our  prices  for  books  are  for  the  latest  editions  published. 

421 


422 


W.  & L.  E.  GURLEY, \ TROY,  N.  K 


ARCHITECTURE,  CARPENTRY,  AND  BUILDING. 

Price. 

BALDWIN,  W.  J.  Steam- Heating  for  Private  Houses  and  large 

Buildings.  12mo.  384  pages.  131  illustrations $2.50 

BERG,  W.  G.  Buildings  and  Structures  of  American  Railroads. 

4to.  534  pages.  700  illustrations 5.00 

BULLOCK,  J.  Rudiments  of  Architecture  and  Building.  8vo. 

468  pages.  250  illustrations 2.50 

FREITAG,  J.  K.  Architectural  Engineering,  and  High  Building 

Construction.  8vo.  421  pages.  196  illustrations 3.50 

GOULD,  L.  D.  Carpenters’  and  Builders’  Assistant.  8vo 2.50 

HATFIELD,  R.  G.  The  American  House-Carpenter.  8vo.  685 

pages.  450  illustrations 5.00 

HURST,  J.  T.  Hand-Book  for  Architectural  Surveyors 2.00 

KEMP,  EDWARD.  Landscape  Gardening.  403  pages.  204 

illustrations.  12mo : 2.50 

KIDDER,  F. . E.  Building  Construction  and  Superintendence. 

Parti.  Masons’  Work.  8vo.  421  pages.  260  illustrations..  4.00 
KIDDER,  F.  E.  Building  Construction  and  Superintendence. 

Part  II.  Carpenters’  Work.  8vo.  544  pages.  524  illustra- 
tions  4.00 

WOODWARD,  G.  E.  Suburban  and  Country  Houses.  70  illus- 
trations..  1.00 

ASTRONOMY. 

BOWDITCH,  N.  American  Practical  Navigator.  An  Epitome 

of  Navigation  and  Nautical  Astronomy.  8vo $2.75 

CHAUVENET,  WM.  Spherical  and  Practical  Astronomy  ; and 
the  Theory  and  Use  of  Fixed  Astronomical  Instruments.  2 

vols.,  royal  8vo 7.00 

LOOMIS,  E.  Practical  Astronomy,  with  Astronomical  Tables. 
Description  of  instruments  required.  Method  of  determining 
time,  latitude,  and  longitude,  with  the  computation  of  eclipses 
and  occultations.  For  the  use  of  amateur  observers,  practical 

surveyors  and  engineers.  505  pages.  37  tables.  8vo 2.00 

NAUTICAL  Almanac.  Published  by  authority  of  the  Secretary  of 

the  Navy,  Washington.  Each  year... 75 

NAUTICAL  Almanac  and  Ephemeris.  Large  8vo.  Each  year...  1.50 
NEWCOMB,  S.  Popular  Astronomy,  with  112  engravings  and  5 

maps  of  the  stars.  8vo 2.50 

PROCTOR,  R.  A.  Half-Hours  with  the  Telescope.  12mo.  Illu- 

trated 1.25 

PROCTOR,  R.  A.  Half-Hours  with  the  Stars.  A plain  and  easy 
guide  to  the  knowledge  of  the  constellations,  with  explanation 
of  each  map.  True  for  every  year.  Demy  4to 2.00 


W.  dr*  L.  E.  GURLEY,  TROY,  N.  Y. 


423 


BRIDGES,  ROOFS,  ETC. 

Price. 

BENDER,  C.  B.  Principles  of  Economy  in  the  Design  of  Metallic 

Bridges,  including  Cantilever  Bridges.  195  pages.  12  plates  $2.50 
BOLLER,  A.  P.  Practical  Treatise  on  the  Construction  of  Iron 

Highway  Bridges.  Illustrated.  8vo 2.00 

BURR,  WM.  H.  Stresses  in  Bridges  and  Roof  Trusses,  Arched 
Ribs  and  Suspension  Bridges.  501  pages.  Illustrations  and 

13  plates.  8vo 3.50 

FOSTER,  W.  C.  Wooden  Trestle  Bridges.  The  present  practice 
on  American  railroads.  4to.  255  pages.  164  illustrations. 

47  plates 5.00 

GREENE,  C.  E.  Roof  Tresses.  Diagrams  for  Steady  Load, 

Snow  and  Wind.  8vo 1.25 

GREENE,  C.  E.  Bridge  Trusses.  Single,  Continuous  and 
Draw-Spans  ; Single  and  Multiple  Systems  ; Straight  and  In- 
clined Chords.  8vo.  Illustrated.  10  plates 2.50 

GREENE,  C.  E.  Arches  in  Wood,  Iron  and  Stone,  for  Roofs, 
Bridges  and  Wall  openings  ; Arched  Ribs  and  Braced  Arches, 
Stresses  from  Wind  and  change  of  Temperature.  8vo.  190 

pages.  60  illustrations.  8 plates 2.50 

HAUPT,  H.  Bridge  Construction.  Practical  illustrations.  8vo...  3.50 

HAUPT,  H.  Military  Bridges  ; Trestle  arid  Truss  Bridges.  8vo.  6.50 
MERRILL,  W.  E.  Iron  Truss  Bridges  for  Railways.  With  a 

comparison  of  prominent  Truss  Bridges.  Illustrated.  4to 5.00 

MERRIMAN,  M.  Text  Book  on  Roofs  and  Bridges.  Part  1. 

Stresses  in  Simple  Trusses.  8vo.  183  pages.  105  illustrations  2.50 
MERRIMAN,  M.  Text  Book  on  Roofs  and  Bridges.  Part  2. 

Graphic  Statics.  8vo.  234  pages.  138  illustrations 2.50 

MERRIMAN,  M.  Text  Book  on  Roofs  and  Bridges.  Part  3. 

Bridge  Design.  8vo.  425  pages.  68  illustrations  and  18 

plates .* 2.50 

MERRIMAN,  M.  Text  Book  on  Roofs  and  Bridges.  Part  4. 

Higher  Structures.  8vo.  276  pages.  136  illustrations 2.50 

PRELINI,  CHARLES.  Tunneling ; A Practical  Treatise  on 
Earth,  Rock  and  Submarine  Tunneling.  8vo.  311  pages. 

150  illustrations 3.00 

SPIREVE,  S.  H.  Strength  of  Bridges  and  Roofs.  With  practical 

applications  and  examples.  89  cuts.  8vo 3.50 

WHIPPLE,  S.  Bridge  Building.  Practical  Treatise  on  Iron  and 

Wooden  Bridges.  8vo.  352  pages.  Illustrated 3.00 

WRIGHT,  C.  H.,  AND  WING,  C.  B.  Manual  of  Bridge  Draft- 
ing. With  folding  plates  and  blue-print  diagrams.  4to 4.00 


424 


W.  &>  L.  E.  GURLEY , TROY,  N.  Y. 


CHEMISTRY,  PHYSICS,  ETC. 

Price. 

ATTFIELD,  J.  Chemistry,  General,  Medical,  and  Pharmaceuti- 
cal. 12mo $2.75 

BAYLEY,  THOS.  A Pocket-book  for  Chemists,  Chemical  Manu- 
facturers, Metallurgists,  Dyers,  Distillers,  Brewers,  etc.  32mo.  2.00 

CHURCH,  A.  H.  The  Laboratory  Guide  ; Practical  Chemistry 

for  Colleges  and  Schools,  and  Agricultural  Students.  12mo...  2.50 

CLASSEN-HERRICK-BOLTWOOD.  Quantitative  Chemical 

Analysis  by  Electrolysis.  8vo.  301  pages.  Illustrated 3.00 

EISSLER,  M.  Modern  ‘High  Explosives.  8vo.  395  pages. 

Illustrated 4.00 

FLETCHER,  E.  L.  Practical  Instructions  in  Quantitative  Assay- 
ing with  the  Blowpipe.  12mo 1.50 

FRESENIUS-WELLwS.  Qualitative  Chemical  Analysis.  Revised 

edition.  8vo.  748  pages 5.00 

FRESENIUS,  C.  R.  Quantitative  Chemical  Analysis.  Revised 
by  Prof.  O.  D.  Allen  and  Prof.  S.  W.  Johnson.  883  pages. 

8vo.  107  illustrations 6.00 

GANOT-ATKINSON.  Elementary  Treatise  on  Physics,  experi- 
mental and  applied.  8vo.  1057  illustrations 5.00 

PLATTNER,  T.  H.  Blowpipe  Analysis.  Illustrated.  560  pages. 

8vo 5.00 

PLYMPTON,  G.  W.  The  practical  use  of  the  Blowpipe.  12mo. 

Illustrated 1.50 

PRESCOTT,  A.  B.  First  Book  in  Qualitative  Chemistry.  12mo.  1.50 

WILSON,  E.  B.  Cyanide  Processes.  12mo.  116  pages 1.50 

CONSTRUCTIONS,  STRENGTH  OF  MATERIALS,  ETC. 

BAKER,  I.  O.  Treatise  on  Masonry  Construction.  With  160 

engravings,  87  tables.  8vo.  600  pages $5.00 

BURR,  WM.  H.  Elasticity  and  Resistance  of  the  Materials  of 

Engineering.  753  pages.  8vo.  Illustrated 5.00 

BYRNE,  A.  T.  Highway  Construction.  The  Location,  Con- 
struction and  Maintenance  of  Roads,  Streets  and  Pavements. 

895  pages.  306  illustrations.  90  tables.  8vo 5.00 

BYRNE,  A.  T.  Inspection  of  Materials  and  Workmanship  em- 
ployed in  construction.  540  pages 3.00 

CLARK,  D.  K.  Tramways  ; their  Construction  and  Working. 

400  illustrations  and  13  plates.  8vo 9.00 

DUBOIS,  PROF.  A.  J.  Strains  in  Framed  Structures.  With 
numerous  practical  Applications  to  Cranes,  Bridge,  Roof  and 
Suspension  Trusses,  Braced  Arches,  Pivot  and  Draw-Spans, 
Continuous  Girders,  etc.  Fully  illustrated.  4to.  618  pages..  10.00 
FAIRCHILD,  C.  B.  Street  Railways ; Construction,  Operation 

and  Maintenance.  4to.  472  pages.  700  illustrations 4.00 


W.  & L.  E.  GURLEY,  TROY,  N.  Y.  425 

Price. 

GILLMORE,  GEN.  Q.  A.  Treatise  on  Limes,  Hydraulic  Ce- 
ments and  Mortars.  Papers  on  Practical  Engineering,  U.  S. 

Engineer  Department.  8vo.  334  pages $4.00 

HATFIELD,  R.  G.  Theory  of  Transverse  Strains  in  the  Con- 
struction of  Buildings,  Iron  Girders,  Roofed  Trusses,  etc.  8vo.  5.00 

HOWE,  M.  A.  Retaining-Walls  for  Earth.  12mo ...  1.25 

PAINE,  G.  H.  Roadmaster’ s Assistant.  A Manual  of  Mainte- 
nance of  Way.  16mo 1.50 

PATTON,  W.  M.  Practical  Treatise  on  Foundations.  8vo.  410 

pages.  23  folding  plates 5.00 

JERVIS,  J.  B.  Railway  Construction  and  Management.  12mo...  2.00 

JOHNSON,  J.  B.  The  Designing  of  Modern  Framed  Structures. 

4to.  527  pages.  450  illustrations.  40  plates 10.00 

SHIELDS,  J.  E.  Notes  on  Engineering  Construction,  and  descrip- 
tion of  the  materials  employed  in  Tunneling,  Bridging,  Canal 

and  Road  Building,  etc.  Illustrated.  12mo  1.50 

SMITH,  J.  B.  Cable  Tramways,  as  applied  to  the  working  of 

Street  and  other  Railways.  Illustrated.  4to 2.50 

SPALDING,  F.  P.  Text-Book  on  Roads  and  Pavements.  12mo.  2.00 

TRATMAN,  E.  E.  R.  Railway  Track  and  Track-Work.  472 

pages.  226  illustrations.  8vo 3.00 

WEBB,  WALTER  L.  Railroad  Construction  ; Theory  and  Prac- 
tice. 8vo.  456  pages.  159  illustrations.  18  plates 4.00 

WOOD,  DE  VOLSON.  Resistance  of  Materials,  and  an  appendix 

on  the  Preservation  of  Timber.  8vo.  314  pages.  Illustrated  2.00 
WRIGHT,  A.  M.  American  Street  Railways ; their  Construction, 

Equipment,  and  Maintenance.  300  pages.  12mo 5.00 

DRAWING. 

ANDRE,  G.  G.  Draughtsman’s  Hand-book  of  Plan  and  Map 
Drawing.  With  instructions  for  Engineering,  Architectural 

and  Mechanical  Drawing.  Illustrated.  33  plates.  8vo ($3.75 

ANTHONY,  G.  C.  Mechanical  Drawing.  98  pages.  32  plates  1.75 

ANTHONY,  G.  C.  Machine  Drawing.  56  pages.  18  plates 1.75 

APPLETON’S  Cyclopedia  of  Drawing.  New  edition,  enlarged. 

8vo.  Fully  illustrated 10.00 

BROWN,  G.  E.  Ferric  and  Heliographic  Processes.  Illustrated..  1.00 
CHURCH,  A.  E.  Elements  of  Descriptive  Geometry  ; Spherical 
Projections,  Shades  and  Shadows,  Perspective  and  Isometric 

Projections.  8vo. , and  Atlas  of  Plates,  4to 3.50 

CROMWELL,  J.  H.  System  of  Easy  Lettering 50 

ESSER.  Draughtsman’ s Alphabets.  Oblong 1.50 

JACOBY,  H.  S.  Text-Book  on  Plain  Lettering.  8vo.,  oblong. 

82  pages.  48  plates 3.00 

HULME,  F.  E.  Drawing-Instruments,  and  How  to  Use  Them. 

12mo.  152  pages.  70  illustrations 1.50 


426 


IV.  & L E.  GURLEY,  TROY,  N.  Y. 


Price. 

MAHAN,  D.  H.  Industrial  Drawing ; Comprising  the  Descrip- 
tion and  Uses  of  Drawing-Instruments,  the  Construction  of 
Plane  Figures,  the  Projections  and  Sections  of  Geometrical 
Solids,  Architectural  Elements,  Mechanism  and  Topographical 
Drawing.  Revised  by  Prof.  D.  F.  Thompson.  1 vol.  209 


pages,  and  Atlas  of  Plates.  8vo.  New  edition $3.50 

MAXTON,  J.  Manual  of  Engineering  Drawing.  12mo 1.40 

MINIFIE,  WM.  Mechanical  Drawing,  including  an  Introduction 
to  Isometrical  Drawing,  and  an  Essay  on  Linear  Perspective 

and  Shadows.  200  illustrations.  8vo 4.00 

MINIFIE,  WM.  Geometrical  Drawing  — an  abridgment  of 

“Mechanical  Drawing.”  12mo 2.00 

REED,  H.  A.  Topographical  Drawing  and  Sketching,  and  Photog- 
raphy applied  to  Surveying.  226  pages.  Illustrated  and 

with  25  plates.  4to 5.00 

REINHARDT,  C.  W.  Lettering  for  Draughtsmen,  Engineers  and 

Students,  8vo.  Oblong 1.00 

REINHARDT,  C.  W.  Technic  of  Mechanical  Drawing.  8vo. 

oblong.  36  pages.  62  illustrations.  10  plates 1.00 

ROSE,  JOSHUA.  Mechanical  Drawing  Self-Taught,  Elementary 

Instruction  in  Practical  Drawing.  330  illustrations.  8vo 4.00 

SMITH,  R.  S.  Manual  of  Topographical  Drawing.  Revised  and 

enlarged  by  Chas.  McMillan,  C.  E.  Illustrated.  8mo 2.50 

STANLEY,  W.  F.  Mathematical  Drawing-Instruments  ; with 

hints  upon  Drawing  and  Coloring.  12mo.  ...... • 2.00 

TUTHILL,  W.  B.  Practical  Lessons  in  Architectural  Drawing. 

8vo.,  and  with  33  plates 2.50 

WARREN,  S.  E.  Drafting-Instruments  and  Operations.  12mo...  1.25 

WARREN,  S.  E.  Elements  of  Machine  Construction  and  Draw- 
ing. 2 vols.  8vo.  Text  and  plates... 7.50 

WARREN,  S.  E.  Free-hand  Drawing.  12mo 1.00 

WARREN,  S.  E.  General  Problems  of  Shades  and  Shadows.  8vo.  3.00 

WARREN,  S.  E.  Manual  of  Projection  Drawing.  12mo 1.50 

WARREN,  S.  E.  Manual  of  Linear  Perspective.  12mo 1.00 

WARREN,  S.  E.  New  Descriptive  Geometry.  8vo 3.50 

WARREN,  S.  E.  Plane  Problems  in  Elementary  Geometry. 

12mo 1.25 


ELECTRICITY,  TELEGRAPHY,  ETC. 

ATKINSON,  P.  Electric  Lighting  ; including  Electric  Genera- 
tion, Measurement,  Storage,  and  Distribution.  264  pages.  104 


illustrations.  12mo $1.50 

CROCKER,  F.  B.  Electric  Lighting ; a Practical  Treatise  for 

Electricians  and  Students.  8vo.  437  pages.  Illustrated 3.00 


CROCKER,  F.  Be,  AND  WHEELER,  S.  S.  Management  of 

Dynamos  and  Motors.  12mo.  210  pages.  100  illustrations..  1.00 


W.  & L.  E.  GURLEY,  TROY,  N.  Y.  427 

Price. 

DAWSON,  PHILIP.  Electric  Railways  and  Tramways.  Prac- 
tical Hand-Book  of  Construction  and  Operation.  Small  4to. 

705  pages.  530  illustrations.  183  tables  $12.50 

DAWSON,  PHILIP.  Engineering  and  Electric  Traction  Pocket- 

Book.  16mo.  1,354  pages.  1,300  illustrations.  947  tables...  4.00 
FISKE,  LIEUT.  B.  A.  Electricity  in  Theory  and  Practice  ; ele- 
ments of  electrical  engineering.  270  pages.  176  illustrations.  8vo.  2.50 
FOSTER,  H.  A.  Electrical  Engineer’s  Pocket-Book.  16mo. 

1,000  pages.  Fully  illustrated 5.00 

HOMANS,  J.  E.  A B C of  the  Telephone.  A Practical  Treatise. 

8vo.  352  pages.  269  illustrations 1.00 

HERRICK,  A.  B.  Practical  Electric  Railway  Hand-Book.  300 

pages.  Illustrated 2.00 

LOCKWOOD,  T.  D.  Electricity,  Magnetism,  and  Electric  Tele- 
graphy. General  Information  for  Electrical  Students,  Operators, 

and  Inspectors.  8vo.  378  pages.  152  illustrations 2.50 

POPE,  F.  L.  Modern  Practice  of  Electric  Telegraph.  8vo. 

Illustrated 1.50 

PRESCOTT,  G.  B.  Electricity  and  the  Electric  Telegraph.  2 

vols.  8vo.  Illustrated 7.00 

SLOANE,  T.  O’C.  Standard  Electrical  Dictionary.  624  pages. 

350  illustrations.  12mo /. 3.00 

SLOANE,  T.  O’C.  Arithmetic  of  Electricity.  12mo 1.00 

SLOANE,  T.  O’C.  Electricity  Simplified.  Illustrated.  12mo...  1.00 

SPRAGUE,  J.  T.  Electricity  ; its  Theory,  Sources,  and  Applica- 
tions. New  edition,  with  numerous  illustrations.  647  pages..  6.00 
URQUHART,  J.  W.  Dynamo  Construction.  A practical  Hand- 
book. 352  pages.  113  illustrations.  12mo 3.00 

GEOLOGY,  MINING,  AND  METALLURGY. 

BAUERMAN,  H.  Metallurgy  of  Iron.  Outlines  of  the  History 

of  Iron  Manufacture,  Analysis  of  Iron  Ores,  etc.  12mo $2.00 

BOWIE,  A.  J.,  Jr.  Practical  Treatise  on  Hydraulic  Mining,  with 
Description  of  the  Use  and  Construction  of  Ditches,  Flumes, 
Wrought-iron  Pipes,  and  DamS  ; Flow  of  Water  on  Heavy 
Grades,  and  its  Applicability,  under  High  Pressure,  to  Mining. 

313  pages.  72  illustrations.  52  tables.  8vo i 5.00 

COAL  and  Metal  Miners’  Pocket-Book.  12mo.  600  pages.  300 

illustrations 3.00 

DANA,  E.  S.  Minerals  and  How  to  Study  Them.  12mo.  380 

pages.  319  illustrations 1.50 

DANA,  E.  S.  Text-Book  of  Mineralogy.  8vo.  593  pages. 

1,008  illustrations 4.00 

DANA,  J.  D.  Manual  of  Geology,  treating  especially  of  American 

Geological  History.  8vo . 6.00 

DANA,  J.  D.  Manual  of  Mineralogy  and  Petrography.  12mo. 

517  pages.  Illustrated 2,00 


428 


IV.  &>  L.  E.  GURLEY,  TROY,  N.  Y. 


Price. 

DANA,  J.  D.  Text-Book  of  Geology.  12mo $2.50 

FURMAN,  H.  VAN  F.  Manual  of  Practical  Assaying.  8vo. 

467  pages . ..  3.00 

IHLSENG,  M.  C.  Manual  of  Mining,  Mining  Engineering, 

Practical  Mining.  563  pages.  262  illustrations.  8vo 4.00 

OSBORN,  H.  S.  Prospector’s  Field-Book  and  Guide.  New 

Edition.  12mo.  296  pages.  Illustrated 1.50 

PHILLIPS,  J.  S.  Explorers’  and  Assayers’  Companion.  Vol.  I, 

Rocks,  Veins,  Testing,  and  Assaying.  8vo 6.00 

VAN  WAGENEN,  T.  F.  Manual  of  Hydraulic  Mining,  for  the 

Use  of  the  Practical  Miner.  18mo / 1.00 

WILSON,  E.  B.  Practical  Mine  Ventilation.  16mo.  Illustrated  1.25 

HYDRAULIC  AND  SANITARY  ENGINEERING. 

ADAMS,  J.  W.  Sewers  and  Drains  for  Populous  Districts.  Rules 
and  Formulas  for  the  Dimensions  and  Construction  of  Works  of 

Sanitary  Engineers.  8vo.  228  pages.  Illustrated $2.50 

BILLINGS,  W.  R.  Details  of  Water- works  Construction.  8vo. 

Illustrated 2.00 

BOX,  THOMAS.  Practical  Hydraulics  ; Rules  and  Tables  for  the 

Use  of  Engineers,  etc.  12mo.  100  pages.  49  illustrations...  2.00 

FANNING,  J.  T.  A Practical  Treatise  on  Water-Supply  Engineer- 
ing ; relating  to  the  Hydrology,  Hydrodynamics,  and  Practical 
Construction  of  Water-works  in  North  America.  8vo.  650 

pages.  200  illustrations.  121  tables 5.00 

FOLWELL,  A.  P.  Water-Supply  Engineering.  8vo.  562  pages. 

95  illustrations  and  19  plates 4.00 

FOLWELL,  A.  P.  Sewerage  ; Designing,  Construction,  and  Main- 
tenance of  Sewerage  Systems.  8vo.  445  pages.  Illustrated...  3.00 
FRENCH’S  Principles,  Process  and  Effects  of  Draining  Lands. 

Over  100  illustrations.  12mo 1.50 

FRIZELL,  J.  P.  Water-Power  ; Development  and  Application 
of  the  Energy  of  Flowing  Water.  8vo.  589  pages.  250 

illustrations....  ’ 5.00 

GOODRICH,  W.  F.  Economic  Disposal  of  Towns’  Refuse.  8vo. 

340  pages.  Illustrated 3.50 

HILL,  J.  W.  Purification  of  Public  Water  Supplies.  8vo.  304 

pages.  Illustrated 3.00 

LEFFEL,  JAS.  Race  and  Reservoir  Embankments,  Gauging 

Water-Supply,  Construction  of  Mill  Dams,  etc.  8vo 2.50 

MERRIMAN,  M.  Treatise  on  Hydraulics,  Hydrostatics,  Hydrau- 
lic Motors,  etc.  Numerous  Tables  and  Diagrams.  427  pages. 

122  illustrations.  25  tables.  8vo 4.00 

NEWELL,  F.  H.  Irrigation  in  the  United  States.  The  Methods, 
Advantages,  and  Irrigation  Law.  8vo.  417  pages.  156 
illustrations 2?0Q 


IV.  &*  L.  E.  GURLEY,  TROY,  N.  Y.  429 

Price. 

OGDEN,  H.  N.  Sewer  Design.  12mo.  234  pages.  Illustrated  $2.00 

RAFTER,  G.  W.,  and  BAKER,  M.  N.  Sewage  Disposal  in  the 

United  States.  600  pages.  Illustrated  and  plates.  8vo 6.00 

STALEY-PIERSON.  The  Separate  System  of  Sewerage.  Theory 

and  Construction.  Illustrated.  8vo.  280  pages.  21  tables.  3.00 
STEWART,  H.  Irrigation  for  the  Farm,  Garden,  and  Orchard. 

Illustrated.  276  pages.  12mo 1.60 

TURNEAURE-RUSSELL.  Public  Water-Supplies.  Require- 
ments and  Construction.  8vo.  746  pages.  231  illustrations..  5.00 
WARING,  G.  E.  Draining  for  Profit  and  Health.  How  to  Lay 

Out  and  Construct  a System  of  Drains.  Illustrated.  12mo...  1.50 

WARING,  G.  E.  Modern  Methods  of  Sewage  Disposal.  252 

pages.  Illustrated..  12mo 2.00 

WARING,  G.  E.  Sanitary  Drainage  of  Houses  and  Towns. 

12mo.  .• 2.00 

WARING,  G.  E.  Sewerage  and  Land  Drainage.  406  pages,  and 

30  plates.  Quarto 6.00 

WEGMANN,  E.,  Jr.  The  Design  and  Construction  of  Masonry 

Dams.  250  pages  and  97  plates.  14  tables.  4to 5.00 

WILSON,  H.  M.  Manual  of  Irrigation  Engineering.  Hydrog- 
raphy. Canals  and  Canal  Work.  Storage  Reservoirs.  8vo. 

538  pages.  124  illustrations.  39  plates 4.00 

WEISBACH,  J.  Hydraulics  and  Hydraulic  Motors,  with  practical 
examples  for  the  calculation  and  construction  of  Water-Wheels, 
and  a discussion  of  the  various  forms  of  Turbines,  translated 
from  Weisbach’s  Mechanics,  by  A.  J.  Du  Bois.  8vo.  675 
pages.  591  illustrations 5.00 

MACHINERY  AND  MECHANICS. 

APPLETON’S  Dictionary  of  Mechanics.  5,000  engravings.  Large 

8vo.  2 vols.,  sheep  binding $15.00 

BOURNE,  JOHN.  A Catechism  of  the  Steam-Engine.  12mo...  2.00 

BOURNE,  JOHN.  Hand-Book  of  the  Steam-Engine.  A key  to 

the  “ Catechism  of  the  Steam-Engine.”  Illustrated.  12mo...  1.75 

BROWN  & SHARPE  Mfg.  Co.  Gear  Wheels  and  Gearing. 

Practical  Treatise,  with  Tables.  Illustrated.  8vo 1.00 

CLARK,  D.  K.  A Manual  of  Rules,  Tables,  and  Data  for  Mechan- 
ical Engineers,  based  on  the  most  recent  investigations.  Illus- 
trated with  numerous  Diagrams.  Large  8vo.  1,012  pages 5.00 

COOPER,  J.  H.  Use  of  Belting  for  Transmission  of  Power.  8vo. 

Illustrated 3.50 

FITZGERALD,  W.  S.  The  Boston  Machinist.  Illustrated 1.00 

FORNEY,  M.  N.  Catechism  of  the  Locomotive.  709  pages.  500 

illustrations.  8vo 3.50 

GOODEVE,  T.  M.  Text-book  on  the  Steam-Engine.  12mo.  143 

illustrations 2.00 


430  W.  <5*  L.  E.  GURLEY,  TROY,  N.  Y. 

Price. 

HEMENWAY,  F.  F.  Indicator  Practice  and  Steam-Engine  Econ- 
omy. 12mo.  184  pages.  Illustrated $2.00 

HUGHES,  WM.  C.  American  Miller  and  Millwright’s  Assistant. 

lSmo 1.50 

ISHERWOOD,  B.  F.  Engineering  Precedents  for  Steam  Machin- 
ery. Arranged  in  the  most  practical  and  useful  manner  for 

Engineers.  Illustrated.  8vo 2.50 

PRAY,  THOS.,  Jr.  Twenty  Years  with  the  Indicator.  286 

pages.  175  illustrations.  8vo 2.50 

ROPER,  S.  Hand-book  of  Land  and  Marine  Engines,  including 

their  Modeling,  Construction,  and  Management.  12mo 3.50 

ROPER,  S.  Hand-book  of  the  Locomotive ; Construction  and 

Management  of  Locomotive  Engines  and  Boilers.  12mo 2.50 

SCHUMANN,  F.  A Manual  of  Heating  and  Ventilation.  Em- 
bracing a Series  of  Tables  and  Formulae  for  dimensions  of 
heating,  flow  and  return  pipes  for  steam  and  hot-water  boilers, 

flues,  etc.  12mo.  Illustrated 1.50 

THURSTON,  R.  H.  Manual  of  Steam  Boilers ; Design,  Con- 
struction and  Operation.  8vo.  883  pages.  244  illustrations..  5.00 
THURSTON,  R.  H.  Manual  of  the  Steam-Engine.  Part  I. 

Structure  and  Theory.  8vo.  1,000  pages.  Illustrated 6.00 

THURSTON,  R.  H.  Manual  of  the  Steam-Engine.  Part  II. 

Design,  Construction,  and  Operation.  8vo.  Illustrated 6.00 


POCKET-BOOKS,  TABLES,  ETC. 

ALLEN,  C.  F.  Railroad  Curves  and  Earthwork,  with  tables  and 

diagrams.  12mo.  194  pages $2.00 

BOILLEAU,  J.  T.  Traverse  Tables  ; showing  difference  of  lati- 
tude and  departure  to  every  minute  of  the  quadrant.  8vo 5.00 

BRUHNS,  Dr.  Manual  of  Logarithms  to  seven  places  of  Deci- 
mals. 8vo 2.50 

BURT,  W.  A.  Key  to  the  Solar  Compass,  and  Surveyors’  Com- 
panion. All  the  rules  necessary  for  use  in  the  field ; Linear 
Surveys  and  Public  Land  System  of  the  United  States,  Notes 
on  the  Barometer,  suggestions  for  an  outfit  for  a survey  of  four 

months,  etc.  202  pages 2.50 

BUTTS,  EDWARD.  Civil  Engineers’  Field-Book ; designed  for 

the  Locating  Engineer.  With  numerous  tables 2.50 

CLEVENGER,  S.  V.  A treatise  on  the  method  of  Government 
Surveying.  With  complete  Mathematical,  Astronomical,  and 
Practical  Instructions,  for  the  use  of  United  States  Surveyors...  2.50 

COX,  WM.  The  Stadia  Computer 75 

CRANDALL,  C.  L.  Railway  and  other  Earthwork  Tables.  8vo..  1.50 

CROCKETT,  C.  W.  Logarithmic  and  Trigonometric  Tables 1.25 


W.  & L.  E.  GURLEY,  TROY,  N.  Y.  431 

Price. 

DAVIS,  A.  P.  Elevation  and  Stadia  Tables.  8vo $1.00 

GODWIN,  H.  C.  Railroad  Engineers’  Field-Book  on  Exploring, 

Location  and  Construction.  357  pages.  Illustrated.  20  tables  2.50 
GURDEN,  R.  L.  Traverse -Tables  ; Computed  to  four  places  of 
decimals  and  for  every  minute  of  angle  up  to  100  of  distance. 

Size  9x  14,  half  morocco 7.50 

HAMILTON,  W.  G.  Useful  Information  for  Railway  Men.  562pp.  2.00 

HASWELL,  C.  H.  Engineers’  and  Mechanics’  Pocket-Book. 
Tables,  Rules  and  Formulas  Pertaining  to  Mechanics,  Mathe- 
matics and  Physics,  etc.  988  pages.  12mo 4.00 

HENCK,  J.  B.  Engineers’  Field-Book.  Containing  Formulae  for 
laying  out  Curves,  determining  Frog  Angles,  Leveling,  calcu- 
lating Earthworks.  273  pages.  17  tables 2.50 

HODGMAN,  F.  Surveyors’  Tables  ; being  the  21  tables  as  printed 

in  Hodgman’s  Manual  of  Surveying.  16  mo.  106  pages 1.00 

HOWARD,  C.  R.  Earthwork  Mensuration  on  the  Basis  of  the 

Prismoidal  Formulae.  8vo.  Illustrated 1.50 

HUDSON,  J.  R.  Excavation  and  Embankment  Tables.  8vo 1.00 

JOHNSON,  J.  B.  Stadia  and  Earthwork  Tables.  8vo 1.25 

KENT,  WM.  Mechanical  Engineers’  Pocket-Book.  1100  pages. 

Illustrated.  12mo 5.00 

KIDDER,  F.  E.  Architects’  and  Builders’  Hand-book.  1040 

pages.  500  illustrations 4.00 

MERRIMAN,  M.,  and  BROOKS,  J.  P.  Hand-book  for  Sur- 
veyors. Land  Surveying,  Leveling,  Triangulation,  Topog- 
raphy, Tables 2.00 

MOLESWORTH,  G.  L.  Pocket-Book  of  Formulae  for  Engineers.  2.00 
NYSTROM,  Jo  W.  Pocket-Book  of  Mechanics  and  Engineering..  3.50 
PHILBRICK,  P.  H.  Field  Manual  for  Engineers.  388  pages. 

152  illustrations * 3.00 

SEARLES,  WM.  H.  Field  Engineering.  Railway  Surveying, 
Location,  and  Construction.  503  pages.  108  illustrations. 

31  tables 3.00 

SEARLES,  WM.  H.  The  Railroad  Spiral.  Theory  of  the  Com- 
pound Transition  Curve  reduced  to  practical  Formulae  and 

Rules  for  Application  in  Field  Work.  Illustrated. 1.50 

SHUNK,  W.  F.  The  Field  Engineer.  A handy  book  of  practice 
in  the  Survey,  Location*  and  Track- work  of  Railroads,  con- 
taining a large  collection  of  Rules  and  Tables  applicable  to 
both  the  Standard  and  Narrow  Gauge.  339  pages.  17  tables.  2.50 

SHUNK,  W.  F.  Treatise  on  Railway  Curves 2.00 

STILES,  A.  Tables  for  Field  Engineers.  Designed  for  use  in 
the  field.  Tables  containing  all  the  functions  of  a one  degree 
curve,  from  which  a corresponding  one  can  be  found  for  any 
required  degree,  also  tables  of  natural  sines  and  tangents.  8vo.  2.00 

TRAUTWINE,  J.  C.  Excavations  and  Embankments.  8vo 2.00 

TRAUTWINE,  J.  C.  Railroad  Curves.  192  pages.  14  tables...  2.50 


432 


IV.  <&*  L.  E.  GURLEY,  TROY,  N.  Y. 


Price. 

TRAUTWINE,  J.  C.  Civil  Engineers’  Pocket-Book  of  Mensura- 
tion, Trigonometry,  Surveying  Hydraulics,  Hydrostatics, 
Strength  of  Materials,  Masonry,  Principles  of  Wooden  and 
Iron  Roof  and  Bridge  Trusses,  Stone  Bridges  and  Culverts, 
Trestles,  Pillars,  Suspension  Bridges,  Dams,  Railroads,  Turn- 
outs, Turning  Platforms,  Water  Stations,  Cost  of  Earthwork, 
Foundations,  Retaining  Walls,  etc.  900  pages.  Illustrated...  $5.00 
VEGA,  BARON  VON.  Logarithmic  Tables.  8vo.  575  pages...  2.50 
WADDELL,  J.  A.  L.  De  Pontibus.  A Pocket-Book  for  Bridge 

Engineers,  with  tables  and  plates 3.00 

SURVEYING  AND  ENGINEERING. 

See  also  Pocket-Books,  Tables,  etc. 

BROUGH,  B.  H.  Treatise  on  Mine  Surveying.  For  Managers  of 

Mines  and  Collieries.  8vo.  Illustrated.  302  pages $2.50 

CLARK,  J.  M.  New  System  of  laying  out  Railway  Turnouts. 

12mo 1.00 

CLEEMAN,  T.  M.  Railroad  Engineers’  Practice.  Illustrated. 

12mo. 1.50 

DAVIES,  CHAS.  Elements  of  Surveying  and  Leveling  ; Topog- 
raphy, Railway  Curves,  and  Mining  Surveying.  12mo 2.50 

DORR,  B.  F.  Surveyors’  Guide  and  Pocket  Table-Book.  The 
Rules  cover  every  case  likely  to  occur  in  a surveyor’s  practice, 
and  are  based  on  United  States  laws,  and  have  the  approval  of 

the  Commissioner  of  the  General  Land  Office 2.00 

GILLESPIE’S  SURVEYING.  New  edition  in  two  parts.  Part 
I.  Land  Surveying  and  Direct  Leveling.  8vo.  551  pages. 

Illustrated 2. 50 

GILLESPIE’S  SURVEYING.  New  edition.  Part  II.  Higher 

Surveying.  467  pages.  Illustrated 2.50 

GILLESPIE,  W.  M.  Principles  and  Practice  of  Road-Making. 

12mo 2.50 

GILMORE,  GEN.  Q.  A.  Construction  of  Roads,  Streets  and 

Pavements.  12mo.  258  pages.  70  illustrations 2.00 

HAUPT,  L.  M.  Engineering  Specifications  and  Contracts.  Text- 
book and  Work  of  Reference.  8vo.  Illustrated 3.00 

HAUPT,  L.  M.  The  Topographer  ; his  Instruments  and  Methods. 

Fully  illustrated.  8vo 3.00 

HODGMAN,  F.  Manual  of  Land-Surveying.  The  Law  is  from 
the  Statute  Books  of  the  United  States  and  about  160  decisions 
from  the  highest  courts  in  the  land  ; the  Practice  is  from  the 

best  authorities.  503  pages.  21  tables 2.50 

JEFFERS,  W.  N.  Treatise  on  Nautical  Surveying.  8vo.  Illus- 
trated   5. 00 


IV.  &•  L.  E.  GURLEY,  TROY,  N.  Y.  433 

Price. 

JOHNSON,  J.  B.  Engineering  Contracts  and  Specifications.  452 

pages.  8vo.  Illustrated $3.00 

JOHNSON,  J.  B.  Theory  and  Practice  of  Land  and  Railroad 
Surveying,  including  Hydrography,  Geodetic  and  Mining  Sur- 
veying. 900  pages.  Illustrated.  8vo 4.00 

MAHAN,  D.  H.  A Treatise  on  Civil  Engineering.  Revised  by 

De  Volson  Wood.  8vo.  637  pages 5.00 

McCULLOUGH,  E.  Municipal  Public  Works.  8vo. , paper 

cover.  153  pages 50 

PHELPS,  LIEUT.  H.  Practical  Marine  Surveying.  8vo.  217 

pages.  Illustrated 2.50 

PLANE-TABLE,  and  its  use  in  Topographical  Surveying.  From 

the  papers  of  U.  S.  Coast  Survey.  Illustrated.  8vo 2.00 

RANKINE,  W.  J.  M.  Civil  Engineering,  comprising  Engineering 
Surveys,  Earthwork,  Foundations,  Masonry,  Carpentry,  Metal- 
Works,  Loads,  Railways,  Canals,  Rivers,  Water-works,  Har- 
bors, etc.,  with  tables  and  illustrations.  8vo.  London 6.50 

RAYMOND,  W.  G.  Text-Book  of  Plane  Surveying.  8vo.  485 

pages.  Illustrated 3.50 

ROBINSON’S  Surveying  and  Navigation.  With  use  of  instruments, 
essential  Elements  of  Trigonometry,  Mensuration,  and  the 

necessary  Tables.  Edited  by  Oren  Root,  A.  M.  8vo 2.25 

ROOT,  CAPT.  E.  A.  Military  Topography  and  Sketching.  8vo. 

395  pages.  219  illustrations.  New  edition,  enlarged 2.75 

SIMMS,  F.  W.  Principles  and  Practice  of  Leveling.  With  Law’s 

method  of  laying  out  Curves.  8vo.  215  pages 2.50 

WELLINGTON,  A.  M.  The  Economic  Theory  of  the  Location 

of  Railways.  980  pages.  313  engravings,  204  tables.  8vo....  5.00 

WELLINGTON,  A.  M.  Railway  Earthworks,  with  Diagrams. 

2 vols.  Illustrated 4.00 

WILSON,  H.  M.  Topographic  Surveying,  including  Geographic, 
Exploratory  and  Military  Mapping,  Camping,  Photography, 
etc.  8vo.  910  pages.  181  illustrations  and  18  plates 3.50 


TREATISES  ON  INSTRUMENTS,  ETC. 

BAKER,  I.  O.  Engineers’  Surveying  Instruments.  400  pages. 

86  illustrations.  12mo $3.00 

COX,  WM.  Manual  of  the  Polar  Planimeter 25 

COX,  WM.  Slide-Rule  Manual 50 

CROCKETT,  C.  W.  Explanation  of  Mannheim  Slide-Rule 75 

GURLEY,  W.  & L.  E.  Manual  of  the  Principal  Instruments  used 
in  American  Engineering  and  Surveying.  Latest  edition,  re- 
vised. 446  pages.  Fully  illustrated 50 

HALSEY,  F.  A.  Manual  of  the  Slide-Rule 50 


434 


W.  L.  E.  GURLEY,  TROY,  N.  Y. 


Prick. 

HOARE,  C.  The  Slide-Rule,  and  How  to  Use  It.  With  a slide- 

rule  in  tuck  of  cover $1.00 

LANKESTER,  EDWIN.  Half-Hours  with  the  Microscope 2.00 

MANUAL  of  the  Duplex  and  Mannheim  Slide-Rules 75 

NUGENT,  E.  Treatise  on  Optics.  12mo.  103  illustrations 1.50 

STANLEY,  W.  F.  Surveying  and  Leveling-Instruments.  Fully 

described.  12mo.  552  pages.  345  illustrations 3.00 

MISCELLANEOUS. 

ALEXANDER,  J.  H.  Weights  and  Measures.  Ancient  and 

Modern,  reduced  to  Standard  of  the  United  States.  8vo $3.50 

BENJAMIN,  PARK.  Engineers’  and  Mechanics’  Recipes, 

12mo.  300  pages % 2.00 

CHAUVENET,  W.  Plane  and  Spherical  Trigonometry.  8vo *1.60 

CHAUVENET,  W.  Treatise  on  Elementary  Geometry.  8vo 1.75 

CLARKE,  D.  K.  Fuel  ; its  Combustion  and  Economy.  12mo...  1.50 

CRAIG,  B.  F.  The  Decimal  System  of  Weights  and  Measures 50 

CROCKETT,  C.  W.  Elements  of  Plane  and  Spherical  Trigonom- 
etry, with  Tables 1.50 

DAVIES,  C.  Analytical  Geometry  and  Elements  of  Calculus.  n 

8vo.  In  one  vol 2.25 

DAVIES,  C.  Metric  System 1.00 

GREGORY,  O.  Mathematics  for  Practical  Men.  For  Engineers, 

Surveyors,  and  Architects.  8vo 3.00 

KNIGHT,  E.  H.  American  Mechanical  Dictionary  ; a Description 
of  Tools,  Instruments,  Machines,  and  Engineering,  etc.  4 vols. 

8vo.  Illustrated 27.50 

LIPPINCOTT’S  Pronouncing  Gazetteer  of  the  World.  4to,  sheep  12.00 

ROBINSON’S  Geometry  and  Trigonometry.  8vo 2.25 

WEBSTER’S  Unabridged  Dictionary.  4to,  sheep 12.00 


SCIENCE  SERIES. 

18 MO.  FANCY  BOARDS, , 50  CENTS  EACH. 


No. 

1. — Chimneys  for  P'urnaces,  Fire  Places,  and  Steam  Boilers.  By  R. 
Armstrong,  C.  E. 

3.  — Practical  Designing  of  Retaining  Walls.  By  Arthur  Jacob,  C.  E. 

4.  — Proportion  of  Pins  Used  in  Bridges.  By  Chas.  E.  Bender,  C.  E. 

5.  — Ventilation  of  Buildings.  By  W.  F.  Butler. 

6.  — Designing  and  Construction  of  Reservoirs.  By  A.  Jacob,  A.  B. 

7.  — Surcharged  and  Different  Forms  of  Retaining  Walls.  By  Jas.  S. 

Tate,  C.  E. 

11.  — Theory  of  Arches.  By  Prof.  W.  Allan. 

12.  — Theory  of  Voussoir  Arches.  By*Prof.  W.  E.  Cain. 

13.  — Gases  met  with  in  Coal  Mines.  By  J.  J.  Atkinson. 

14.  — Friction  of  Air  in  Mines.  By  J.  J.  Atkinson. 

15.  — Skew  Arches.  By  Prof.  E.  W.  Hyde. 

17.  — Water  and  Water  Supply.  By  Prof.  W.  H.  Corfield. 

18.  — Sewerage  and  Sewage  Purification.  By  W.  N.  Baker,  Ph.  B. 

19.  — Strength  of  Beams  under  Transverse  Loads.  By  Prof.  W.  Allan. 

20.  — Bridge  and  Tunnel  Centers.  By  E.  S.  Gould,  C.  E. 

22.  — High  Masonry  Dams.  By  John  B.  McMaster,  C.  E. 

23.  — Fatigue  of  Metals  under  repeated  Strains.  From  the  German  of 

Prof.  Spangenburgh,  with  a Preface  by  S.  H.  Shreve,  A.  M. 

25.  — Theory  and  Calculation  of  Continuous  Bridges.  By  M.  Merriman, 

Ph.  D. 

26.  — Practical  Treatise  on  Continuous  Bridges.  By  Charles  Bender,  C.  E. 

31.  — Sanitary  Condition  of  Dwelling  Houses.  By  Geo.  E.  Waring,  Jr. 

32.  — Cable  Making  of  Suspension  Bridge.  By  Hildenbrand,  C.  E. 

33.  — Mechanics  of  Ventilation.  By  Geo.  W.  Rafter,  C.  E. 

34.  — Foundations.  By  Prof.  Jules  Gaudard,  C.  E. 

35.  — Aneroid  Barometer : Its  Construction  and  Use.  By  Geo.  W. 

Plympton. 

37.  — Geographical  Surveying.  By  Frank  De  Yeaux  Carpenter,  C.  E. 

38.  — Maximum  Stresses  in  Frame  Bridges.  By  Prof.  W.  E.  Cain,  A.  M. 

40.  — Transmission  of  Power  by  Compressed  Air.  By  R.  Zahner,  M.  E. 

41.  — Strength  of  Materials.  By  Wm.  Kent,  C.  E. 

42.  — Voussoir  Arches  Applied  to  Stone  Bridges,  Tunnels,  Culverts, 

Groined  Arches,  and  Domes.  By  Prof.  W.  E.  Cain,  C.  E. 

44.  — Turbine  Wheels.  By  Prof.  W.  P.  Trowbridge. 

45.  — Thermodynamics.  By  Prof.  H.  T.  Eddy. 

48. — Theory  of  Solid  and  Braced  Arches.  By  W.  E.  Cain,  C.  E. 

50. — Dwelling  Houses  ; their  Sanitary  Construction  and  Arrangements. 
By  Prof.  W.  H.  Corfield. 


435 


SCIENCE  SERIES. 


436 

No. 

55.  — Sewer  Gases;  their  Nature  and  Origin.  By  A.  de  Varona. 

56.  — Actual  Lateral  Pressure  of  Earthwork.  By  Benj.  Baker,  C.  E. 

58.  — Ventilation  of  Coal  Mines.  By  W.  Fairley. 

59.  — Railroad  Economics.  By  S.  W.  Robinson,  C.  E. 

60.  — Strength  of  Wrought  Iron  Bridge  Members.  By  S.  W.  Robinson, 

C.  E. 

61.  — Potable  Water:  and  Methods  of  Detecting  Impurities.  By  Chas. 

W.  Folkard. 

63. — House  Drainage  and  Sanitary  Plumbing.  By  W.  P.  Gerhard,  C.  E. 
65. — Pocket  Logarithms  to  Four  Places  of  Decimals. 

67. — Hydraulic  Tables.  By  P.  J.  Flynn,  C.  E. 

72. — Topographical  Surveying.  By  Geo.  J.  Specht,  Prof.  A.  S.  Hardy, 
John  B.  McMaster  and  H.  F.  Walling. 

74. — Testing  Machines,  their  History,  Construction  and  Use.  By  Arthur 
V.  Abbott. 

77. — Stadia  Surveying  and  Stadia  Measurements.  By  A.  Winslow. 

80.  — Healthy  Foundations  for  Houses.  By  Glenn  Brown. 

81.  — Water  Meters:  Comparative  Tests  of  Accuracy,  Delivery,  etc. 

By  Ross  E.  Browne. 

82.  — Preservation  of  Timber  by  the  Use  of  Antiseptics.  By  S.  B.  Boul- 

ton, C.  E. 

83.  — Mechanical  Integrators.  By  Prof.  Henry  S.  H.  Shaw,  C.  E. 

84.  — Flow  of  Water  in  Open  Channels,  Pipes,  Conduits,  Sewers,  etc.; 

with  Tables.  By  P.  J.  Flynn,  C.  E. 

87.  — Treatise  on  the  Theory  of  the  Construction  of  Helicoidal  Oblique 

Arches.  By  John  L.  Culley,  C.  E. 

88.  — Beams  and  Girders.  Formulas  for  their  Resistance.  By  Prof. 

P.  H.  Philbrick. 

91. — Leveling;  Barometric,  Trigonometric,  and  Spirit.  By  Prof.  I.  O. 
Baker. 

93.  — Notes  Embodying  Recent  Practice  in  the  Sanitary  Drainage  of 

Buildings.  By  Wm.  Paul  Gerhard,  C.  E. 

94.  — Treatment  of  Sewage.  By  Dr.  C.  Meymott  Tidy. 

95.  — Plate  Girder  Construction.  By  Isami  Hiroi,  C.  E. 

100.  — How  to  Become  an  Engineer.  By  G.  W.  Plympton,  C.  E. 

101.  — The  Sextant  and  other  Reflecting  Mathematical  Instruments.  By 

F.  R.  Brainard,  U.  S.  Navy. 

104. — Van  Nostrand’s  Table  Book  for  Civil  and  Mechanical  Engineers. 

Compiled  by  Prof.  Geo.  W.  Plympton. 

107. — Graphical  Method  for  Swing-Bridges.  By  B.  F.  La  Rue,  C.  E. 
110. — Transition  Curves.  By  W.  G.  Fox. 

114.  — Manual  of  the  Slide-Rule.  By  F.  A.  Halsey. 

115.  — Traverse  Table,  for  distances  between  1 and  100,  and  for  every 

quarter  degree  up  to  90  degrees. 

Any  of  the  “Science  Series”  not  mentioned  in  the  above  list  will  be 
furnished  promptly  on  application. 


THE  RENSSELAER 

POLYTECHNIC  INSTITUTE 

TROY,  N.  Y. 


A School  of  Engineering  and  Science. 

FOUNDED  IN  1824. 


It  is  the  aim  of  the  Institute  to  maintain  the  most  thor- 
ough course  of  engineering  in  this  country.  Its  methods  of 
instruction  are  the  result  of  an  experience  unequaled  by  that 
of  any  similar  school  in  the  world.  The  Course  of  Study 
pursued,  while  not  beyond  the  capacity  of  young  men  of 
average  ability,  is  constantly  adjusted  to  the  progress  of  the 
engineering  profession.  Its  purpose  is  to  equip  students 
to  enter  upon  a general  engineering  practice  and  to  special- 
ize later  as  opportunities  open  before  them.  That  the 
plan  has  been  attended  with  unqualified  success  is  shown 
by  the  Register  issued  annually,  containing  the  business 
address  of  each  living  graduate.  Among  them  will  be  found 
men  eminent  in  every  branch  of  engineering.  It  is,  more- 
over, the  method  of  instruction  pursued  for  other  profes- 
sions. 

It  should  be  stated,  perhaps,  that  Civil  Engineering  is 
understood  to  include  instruction  in  Road  and  Bridge  Con- 
struction, Hydraulics,  Steam  and  Electrical  Engineering, 
Mining  Engineering  and  Assaying. 

The  studies  of  the  course  are  designed  as  a professional 
preparation,  at  once  thorough  and  practical,  for  the  follow- 
ing specialties  of  engineering  practice  : 

437 


438  RENSSELAER  POLYTECHNIC  INSTITUTE. 

The  location,  construction,  and  superintendence  of  public 
works,  as  steam  and  electric  railways,  canals,  water  works, 
etc.;  the  design,  construction  and  management  of  mills,  iron 
works,  steel  works,  chemical  works,  and  pneumatic  works  ; 
the  design  and  construction  of  roofs,  arch  bridges,  girder 
bridges,  and  suspension  bridges  ; the  survey  and  superin- 
tendence of  hydraulic  motors,  air  engines,  electric  motors, 
and  the  various  kinds  of  steam  engines  ; the  design,  con- 
struction and  use  of  machines  in  general,  and  the  determina- 
tion of  their  efficiency  ; the  survey  of  rivers,  lakes  and 
harbors,  and  the  direction  of  their  improvements  ; the  de- 
termination of  latitude,  longitude,  time  and  the  meridian  in 
geographical  explorations,  or  for  other  purposes,  together 
with  the  projection  of  maps  ; the  selection  and  test  of 
materials  used  in  construction  ; the  construction  of  the 
various  kinds  of  geometrical  and  topographical  draw- 
ings. 

A course  of  study  is  also  pursued  in  the  Institute  em- 
bracing more  advanced  instruction  in  Natural  History, 
Chemistry  and  Geology,  leading  to  the  degree  of  Bachelor 
of  Science.  The  first  two  years  are  identical  with  the 
course  in  Civil  Engineering. 

Special  students  in  all  courses,  particularly  in  chemistry 
and  electrical  engineering,  are  also  received. 

There  are  two  terms  in  the  scholastic  year  and  the 
tuition  is  $100  per  term.  Other  expenses  are  largely  within 
the  control  of  individual  students.  Every  effort  is  made 
by  the  management  to  keep  necessary  expenses  within  the 
narrowest  limits,  consistent  with  the  best  opportunities  to 
students,  and  they  have  been  materially  reduced  within  the 
last  few  years. 

Any  one  desiring  a thorough  course  of  study  in  prepa- 
ration for  advanced  professional  work  in  any  department  of 


RENSSELAER  POLYTECHNIC  INSTITUTE,  439 


engineering  is  invited  to  apply  for  further  information  to 
the  President  of  the  Institute. 

“ The  greatest  number  of  the  renowned  hydraulic  and  railroad  engi- 
neers of  America  are  graduates  of  this  school.” — From  the  report  to  his 
government  of  Professor  A.  Riedler  of  the  Royal  Poly  tech  n icum,  at  Berlin . 
{Report  U S.  Commissioner  of  Education  1892-  93.) 

This  famous  Institute  is  by  no  means  local,  as  the  freshman  list  this  year 
contains  the  names  of  students  from  twenty-two  States  of  the  Union,  as  well 
as  from  Cuba  and  South  America,  and  the  graduates  are  leading  men  in 
engineering  and  in  business  all  over  the  world. — The  Railroad  Gazette, 
Febi'uary  22,  1901. 


ROADS, 

- RAILROADS, 

BRIDGES, 


ARCHES, 

STEAM  ENGINES, 

ELECTRIC  ENGINES, 

DYNAMOS, 


DAMS. 


TURBINES. 


FOUNDATIONS, 

WATER  WORKS, 

TUNNELS, 

SEWERS, 

RIVERS, 

CANALS. 


CHEMICAL  ANALYSIS, 

MINERALOGY, 

METALLURGY, 


ASSAYING. 


TABLE  OF  CONTENTS. 


Page. 

Abney  Level  and  Clinometer 231,  275 

Adjustment  of  Architects*  Level 169 

Adjustment  of  Drainage  Level 173 

Adjustment  of  Engineers’  Y-Level 159-164 

Adjustment  of  Engineers’  and  Surveyors’  Transits 19-23 

Adjustment  of  Line  of  Collimation 20,  21,  126,  161 

Adjustment  of  Object-glass  Slide 23,  159,  160 

Adjustment  of  Solar  Attachment 85-88 

Adjustment  of  Solar  Compasses ' 98-100,  134 

Adjustment  of  Surveyors’  Compasses 115-117 

Adjustment  of  Telescopic  Sight 125-127 

Air- Meters . 406-408 

Alidades  for  Plane-Tables 200-204,  274 

Alt-Azimuth, 395 

Alteneder  Drawing-Instruments 302-307 

Aluminum  Instruments 150,  247,  266 

Anemometers 406-408 

Aneroid  Barometers 402-405 

Angle- Mirrors 398 

Architects’  Levels 167-171,267 

Artificial  Horizon 398 

Astronomical  Telescopes 412 

Astronomical  Terms 89-95 

Attachments  and  Extras  for  Compasses 129,  130,  142,  263 

Attachments  and  Extras  for  Transits 48-69,  261,  262 

Ball-Spindle r. 108,  122,  263 

Barometers,  Aneroid 402-405 

Batson  Sketching-Case 205-209,  275 

Battery  for  Current- Meters 216,  275 

Blowpipes 418 

Blue-Print  Paper,  Print-Frames  and  Bath-Trays 365-367 

Books  (blank)  for  Field-Notes 374-376 

Books,  Scientific,  for  Architects,  Draftsmen,  Engineers  and  Sur- 
veyors  421-436 

Boxes  and  Cases  for  Compasses,  Levels  and  Transits 253,  254,  269 

Boxes  and  Cases  for  Drawing- Instruments 294,  307 

Boxwood  Rules  and  Scales 335—342 

Bristol- Board 362 

Bronze  Finish 245 

Brushes  for  Water-Colors 388,  389 

Builders’  Transit 44,  45,  261 


440 


TABLE  OF  CONTENTS. 


441 


Page. 

Celluloid  or  Amber  Goods 331,  332,  345,  346,  348,  352,  354,  358 

Center  Pin 119 

Chains,  American 233-235,  276 

Chains,  Metric  and  Vara 236,277 

Chain-Tapes 237-239,278 

Clamp  and  Tangent 14,  53,  55,  130,  261,  264,  265 

Clinometers 144,  145,  231,  266,  394,  395,  400,  401 

Colors,  Windsor  & Newton’s 383,  385-387 

Compass  Attachments  for  Levels 152,267 

Compasses,  Clinometer 144,  145,  266 

Compasses,  Dial 148-150,  266 

Compasses,  Extras  for 129,  130,  142,  263,  265 

Compasses,  Geologists’ 143,  266 

Compasses,  Miners’  Dip-Needle 146,  147,  266 

Compasses,  Plain 121-123,  .142,  263,  265 

Compasses,  Pocket 132-150,  264-266,  392-396 

Compasses,  Prismatic 395,  396 

Compasses,  Railroad 103-107,  263-265 

Compasses,  Solar 97-102,  132-134,  262,  264 

Compasses,  Vernier 108-120,  139-141,  263,  265 

Compound,  Tangent  Ball-Spindle 122,  263 

Crayon  Pencils  and  Lumber  Crayons 377,  378 

Cross-Section  Books  and  Paper 368,  370-372,  376 

Cross-Staff  Heads * 398 

Cross- Wires 8-11,  250,  253,  254 

Current- Meters 211-224,  261,275 

Current-Meter  Reduction-Tables 217,  218,  220,  221,  224 

Curves  of  Amber,  Rubber  and  Wood 357,  359 


Declination  Arc 62,  86,  133 

Declination  of  Magnetic  Needle 112-114 

Declination  of  the  Sun 65,  75,  76,  90 

Detachable  Telescopes  for  Transits 58, -262 

Diagonal  Prism  for  Eyepiece  of  Telescopes 59,  262 

Dial  Compasses 148-150,  266 

Dip-Needle  Compasses 146,  147,  266 

Diurnal  Variation 114 

Drainage  Levels 172-174,  267 

Drawing-Boards  and  Tables 349,  350 

Drawing-Instruments,  Alteneder 302-307 

Drawing-Instruments,  Brass 322-326 

Drawing-Instruments,  German 308-326 

Drawing-Instruments,  Nickel-plated 324-326 

Drawing-Instruments,  Pivot- Joint 297-307 

Drawing-Instruments,  Swiss 286-301,  327-329 

Drawing-Paper 362-365,368-372 

Dust-Guard  for  Object-glass  Slide  of  Telescopes 12,  262 


442 


TABLE  OF  CONTENTS. 


Page. 

Electric  Current- Meter 222-224,  275 

Electric  Register 212,  216,  275 

Electricity 118 

Ellipses 358 

Empty  Cases  for  Instruments 253,  254,  269,  294,  307 

Engineers’  Levels 152-166,  267 

Engineers’  Transits 6,  25-28,  257,  258 

Erasing-Knives  and  Erasing-Rubber / 379-381 

Excavation  and  Embankment  Tables 376,  430,  431 

Extras  for  Compasses 129,  130,  142,  263,  265 

Extras  for  Transits 48-69 

Eyepiece  of  Telescope,  how  composed , 5-7 

Eyepiece  for  Transit  and  Level  Telescope 5,  7,  253,  254 


Field  Glasses  and  Telescopes  for  Tourists 409-412 

Flagstaff  or  Ranging-Pole 191,  271 

Foreign  Shipments . 246,247 

Geologists’  Compass 143,266 

Gradienter 56,  57,  261 

Graduations  of  Limb  and  Vertical  Circle 16,  262 


Hand-Levels 

Hook-Gauge,  Boyden’s  .... 
Hour-Circle  and  Hour-Arc 

Hydrometers 

Hygrometer 

Hyperbolas 


...  228-231,  275 
...  225,  226,  275 
62,  87,  134,  266 

420 

419 

358 


India  Ink 

Information  to  Purchasers.... 
Ink- Slabs  and  Color- Saucers. 
Ink  for  Drawing  or  Writing  . 

Inverting  Eyepiece 

Ivory  Rules  and  Scales 


383,384 

241-251 

389,390 

365,  373,  383,  384 

7 

334-336,  341 


Lacquering 245 

Latitude  Arc 62,  83,  84,  133,  262 

Latitude-Level 82,  262 

Leather  Cases  and  Pouches 180,  269 

Level  on  Telescope 53,  54,  130,  261,  264 

Level  Vials  and  Spirit  Levels...'. 14,  19,  109,  115,  119,  156,  416,  417 

Leveling  Adopter 122,  142,  263,  265 

Leveling-Instruments,  Architects’  Levels 167-171,  267 

Leveling-Instruments,  Drainage 172-174,  267 

Leveling- Instruments,  Y-Levels 152-171,  267 

Leveling- Rods 181-191,  270,  271 


TABLE  OF  CONTENTS. 


443 


Page. 

Leveling  Tripod  Head 17,  25,  123,  158,  256,  262,  263,  265 

Line  of  Collimation 20,  21,  126,  161 

Locke’s  Hand- Level 230,275 


Magnetic  Needle 

Magnets 

Magnifiers 

Magnifying  Power  of  Telescopes. 
Marking-Pins  and  Timber-Scribe. 

Meters,  Current 

Metric  Aneroid  Barometers 

Metric  Chains  and  Tapes 

Metric  Leveling-Rods  and  Poles. 

Metric  Paper  for  Draftsmen 

Metric  Rules  and  Scales 

Miners’  Dip-Needle  Compasses.. 

Miscellaneous 

Mountain  Transits 

Mucilage .*.... 


13,  66,  101,  106,  112,  115,  116,  118 

418 

55,  262,  413-415 

7,  8 

237,  277 

211-224,  275 

403 

236,  239,  277,  282 

190,  191,  270,  271 

370-372 

340,344 

146,147,266 

254 

29-32,  258 

382 


Object-glass  of  Telescopes 5,  253,  254 

Odometers 399,  400 

Offset-Standard 128,  264 

Oilstones 417 

Opera  and  Field-Glasses 409,  410 

Optical  Axis 9,  10,  127 

Optical  Principles  of  Telescope 5,  7 

Outkeeper Ill 


Packing,  etc 244,  256 

Pantographs 361 

Paper-Cutter.. 373 

Paper,  Drawing  and  Tracing 362-365,  368-372 

Parabolas 358 

Parallel  Rulers 360,  361 

Parchment- Paper 364,  365 

Parts  of  Instruments  liable  to  injury,  prices  of 253,  254 

Passometers 399 

Payment,  Terms  of. 246,251 

Pedometers 399 

Pencils 377 

Pencil-Sharpeners 379 

Pens,  Mapping  and  Writing 318 

Plain  Compasses 121-123,  142,  265 

Plane-Tables 193-204,  272-274 

Planimeters 294,  295 

Platinum  Cross-Wires 8-11,  250,  253,  254,  261 


444  TABLE  OF  CONTENTS. 

Page. 

Plummet-Lamp 60,  262 

Plummets 254,268 

Pocket- Compasses 132-150,  264-266,  392-396 

Pocket-Levels 416 

Polar  Axis 86,  87 

Price-List  253-436 

Prismatic  Compasses 395,  396 

Profile-Books  and  Paper 369,  370,  374 

Protractors  of  Boxwood,  Brass,  Celluloid,  German  Silver,  Horn, 

Ivory,  Paper,  Rubber,  and  Wood 327-335 

Protractors,  Limb,  long  steel  blade 329,  330 

Quick-Leveling  Attachment 262 

Rack  and  Pinion 156,  262,  265 

Railroad  Compasses 103-107,  135-138,  263-265 

Rain-Gauges 420 

Ranging- Poles ^ 191,271 

Reading-Glasses  and  Magnifiers 413-415 

Reconnoissance  Transit 42,  43,  260 

Reflecting  Mirrors  and  Prisms 398 

Reflectors  for  Cross-Wires  and  Limb  of  Transits 16,  59,  262 

Refraction 69,94 

Refractions,  Table  of. 70-74 

Rensselaer  Polytechnic  Institute 437-439 

Repairs  to  Instruments 248-254 

Rod-Level 192,271 

Rods,  Leveling 181-191,  270,  271 

Rubber  Goods 345-347,  352,  354,  357-360,  379-381 

Scales  of  Boxwood,  Ivory,  Paper  and  Metal 334-344 

Section-Liners  355,  356 

Selection  of  Instruments 241 

Sextants 397 

Shifting  Center  for  Leveling- Head  of  Transits 17,  256 

Sights  on  Standards  and  on  Telescope  of  Transits 55,  262 

Sizes  of  Compasses 107,  120,  121,  140 

Sizes  of  Levels 107 

Sizes  of  Transits . 27,  36,  39,  47 

Sketching-Case,  Batson • •••  205—209,  2/5 

Sketch-Blocks  (paper) 368 

Slide-Rules 342,  343 

Slope-Levels 400, 401 

Sockets  of  Levels 104, 158 

Sockets  of  Transits 15,  16,  17,  29,  33,  35,  37,  39 

Solar  Attachment  for  Transits..... 27,  28,  61-69,  262 

Solar  Compasses 97-102,  132-134,  262,  264 


TABLE  OF  CONTENTS, 


445 


Page. 

Solar  Screen 80,  262 

Solar  Transits 27,  28,  31,  40,  41,  258-260 

Special  Notices 241-251,  256,  284,  285 

Spirit-Levels 14,  19,  109,  115,  119,  156,  416,  417 

Spring- Balance  for  Chains  and  Tapes 281 

Stadia  Rods 188,  270 

Stadia  Wires 10,  11,  250,  253,  254 

Staff  Mountings 109,253 

Steel  Rules 344 

Steel  Tapes 237-239,  278,  280-283 

Stencil- Alphabets  and  Figures 390,  391 

Straight-Edges  of  Amber,  Rubber, AVood  and  Steel 344-346 

Striding- Level 86,  262 

Surveyors’  Cross-Staff  Head 398 

Surveyors’  Transits 33-43,  259-261 


Tables,  Drawing 

Tables,  Plane 

Tables,  Reduction  (for  Current- Meters). 

Tables,  Traverse  (books) 

Tacks  for  Drawing-Boards 

Tally-Register 

Tangent  Scale  on  Sight- Vanes 

Tape-Lines,  Metallic 

Tape-Lines,  Steel 

Telescope,  how  composed 

Telescopes  and  Tourists’  Glasses 

Telescopes  for  Vertical  Sighting 

Telescopic  Sight  Attachment 

Thermometers 

Timber- Scribe,  or  Marking-Iron 

Time-Recorder  for  Current- Meters 

Tin-Tubes  for  Drawing-Paper 

Tracing-Cloth  and  Paper 

Trammel  Points 

Transit- Instruments,  Remarks  on 

Transits,  Attachments  for 

Transits,  Builders’  

Transits,  Engineers’ 

Transits,  Light  Mountain  and  Mining 

Transits,  Reconnoissance...: 

Transits,  Solar. 

Transits,  Solar  Attachment  for 

Transits,  Surveyors’ 

Transits,  Vernier 

Transportation 

Traverse-Tables  (books) 


349,350 

193-204 

217,  218,  220,  221,  224 

430,  431,  436 

373 

399,400 

109 

238,279 

237-239,  278,  280-283 


5-7,152 

409-412 

58, 262 

124-130,  264 

418,  419 

277 

215,275 

368 

365 

417,418 

5—23 

48-69,  261,  262 

44,  45,  261 

6,  25-28,  257,  258 

29-32,  258 

42,  43,  260 

27,  28,  31,  40,  41,  258-260 

27,  28,  61-69,  262 

33-43,  259-261 

46,  47,  261 

245 

430,  431,  436 


446 


TABLE  OF  CONTENTS. 


Page. 

Traverse- Table  Board  and  Tripod 203,  274 

Trial  of  Instruments 243 

Triangles  of  Amber,  German  Silver,  Rubber,  Steel  and  Wood...  351-354 

Tripods. 18,  176-179,  195,  267,  268 

T-Squares  of  Amber,  Rubber,  Steel  and  Wood 346-348 


Vara  Chains  and  Tape-Lines 

Variation  Arc  of  Transits 

Variation  of  the  Needle 

Vellum  or  Tracing-Cloth 

Verniers 

Vernier  Compasses 

V ernier  Protractors ' 

Vernier  Transit- Compasses 

Vertical  Arc  and  Vertical  Circle. 


236,  239,  277 

14,  256,  261 

106,  112-114 

365 

15,  112 

108-120,  139-141,  263,  265 

- 328-332 

46,  47,  261 

..  49-52,  130,  256,  261,  264 


Warranty 

Water- Colors 

Water-Glasses 

Weights  of  Compasses 

Weights  of  Levels 

Weights  of  Transits 

Writing-Ink,  Paper  and  Pens,  etc 


242 

#383,  385-387 

389 

102,  107,  120,  122,  138,  140 

167 

...  27,  32,  36,  39,  42,  45,  4Z 

372,  373,  378 


